Luminous Landscape Forum

Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: ErikKaffehr on June 15, 2013, 12:23:43 pm

Title: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 15, 2013, 12:23:43 pm
Hi,

I got my Hasselblad 555ELD with a P45+ sold by Mr. Rib here on LuLa. I am ver satisfied with what I got.

I started a "blog" describing my experience:

http://echophoto.dnsalias.net/ekr/index.php/photoarticles/76-my-medium-format-digital-journey

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Sareesh Sudhakaran on June 16, 2013, 12:16:44 am
Congratulations, Erik! I envy you. :)
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: BernardLanguillier on June 16, 2013, 03:21:04 am
Hi,

I got my Hasselblad 555ELD with a P45+ sold by Mr. Rib here on LuLa. I am ver satisfied with what I got.

I started a "blog" describing my experience:

http://echophoto.dnsalias.net/ekr/index.php/photoarticles/76-my-medium-format-digital-journey

Fascinating development Erik, I am sure you will enjoy your new camera.

Cheers,
Bernard
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 16, 2013, 12:36:42 pm
Hi,

I really do! It works just fine, although I still need some small practical items that were included in the original kit, but not in what I got. Finder masks, front and back covers for camera and so. I'll probably have it all in a few days.

It is actually very nice, not so much different than my Sonys, once it is on a tripod. I of course miss live view for focusing.

Best regards
Erik




Fascinating development Erik, I am sure you will enjoy your new camera.

Cheers,
Bernard

Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: DavidP on June 16, 2013, 01:32:55 pm
I used to have a P25 in V mount it worked fine on an EL body in vertical, there was a sort of hidden or flush fitting alternate release on the other corner to do this. I don't know if they took it off or something. I was alway nervous about doing it in the field.  I have been using a P45+ on another camera system now (V was too hard to focus for me) the P45 is so much better as far as moire hardly ever a problem with it.
Also on the V the older lenses sometimes have sync problems at slow shutter speeds, I think the CFE CFi and CFB lenses are all good to go though. Great system have fun.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: theguywitha645d on June 16, 2013, 01:49:26 pm
Welcome to the club.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 16, 2013, 01:49:28 pm
Hi,

I need to check out the alternate release. I have mostly CF lenses, only one CB (150/4) and that lens will be replaced with a CF soon enough. But so far everything works for me. I got one of the loupe type viewfinders from Hartblei, and it seems to work.

Best regards
Erik

I used to have a P25 in V mount it worked fine on an EL body in vertical, there was a sort of hidden or flush fitting alternate release on the other corner to do this. I don't know if they took it off or something. I was alway nervous about doing it in the field.  I have been using a P45+ on another camera system now (V was too hard to focus for me) the P45 is so much better as far as moire hardly ever a problem with it.
Also on the V the older lenses sometimes have sync problems at slow shutter speeds, I think the CFE CFi and CFB lenses are all good to go though. Great system have fun.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: tho_mas on June 16, 2013, 06:09:57 pm
Hi,

I got my Hasselblad 555ELD with a P45+ sold by Mr. Rib here on LuLa. I am ver satisfied with what I got.

I started a "blog" describing my experience:

http://echophoto.dnsalias.net/ekr/index.php/photoarticles/76-my-medium-format-digital-journey

Best regards
Erik
cool, have fun!

As far as the raw processor goes I'd say the sooner you switch to Capture One (7.1.2) the better.
LR may (or may not) be comparable with C1 in conjunction with more recent P1 backs... but for the old Kodak Sensor backs I feel the Adobe SW is pretty weak with regard to color/look out of the box and also with regard to detail extraction. Especially when you lift the shadows C1 does a better job with your P45+.
When you use C1 do yourself a favour and dial down luminance NR to zero (for ISO50-ISO200) and color NR to around 15-20 (max.) for your P45+ as a camera-preset...
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 16, 2013, 07:35:18 pm
Hi,

Thanks for the suggestions.

I own C1 but I'm much more familiar with LR. Also for me it is a workflow issue. Regarding color I found the Adobe Standard profile lacking but created a DNG profile with which I am quite happy.

I am looking into C1, but we are no friends so far C1 and I.

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ondebanks on June 17, 2013, 11:14:40 am
Congratulations, Erik! Great choice of back...as many pixels as you need, and long-exposure favourite.

I read your blog to date...looking forward to seeing more.

Ray
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: TMARK on June 17, 2013, 11:48:47 am
cool, have fun!

As far as the raw processor goes I'd say the sooner you switch to Capture One (7.1.2) the better.
LR may (or may not) be comparable with C1 in conjunction with more recent P1 backs... but for the old Kodak Sensor backs I feel the Adobe SW is pretty weak with regard to color/look out of the box and also with regard to detail extraction. Especially when you lift the shadows C1 does a better job with your P45+.
When you use C1 do yourself a favour and dial down luminance NR to zero (for ISO50-ISO200) and color NR to around 15-20 (max.) for your P45+ as a camera-preset...


C1 7.1.2 is revelatory on CCD files.  Its like another stop on usable ISO and no annoying jaggies on CCD files, like you get from LR.  Color is awesome. 
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 17, 2013, 04:40:12 pm
Thanks a lot for feedback!

Regarding the blog it will take a couple of days until I have anything substantial. I go abroad for a few days without the Hassy. I did some shooting today, but I am not sure about my conclusions. Perhaps I post a little tomorrow.

What I have seen today is that DoF/diffraction can compensate a lot, but you can do some aggressive sharpening to compensate. What I also have seen is that shooting a grey card for white balance makes Sony and P45+ much closer in color, but B45+ has yellowish greens while Sony is more green and subtle. But I don't really want to jump conclusions.

Than there is the question of LR vs C1. I have used LR since 2006 and I'm quite used to it. C1 has a lot of good features, but I think it is much less consistent than Lightroom. A good thing with C1 is that it handles aliasing artifacts somewhat better than LR.

I also try to make raw images available.

Best regards
Erik

Congratulations, Erik! Great choice of back...as many pixels as you need, and long-exposure favourite.

I read your blog to date...looking forward to seeing more.

Ray

Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Mr. Rib on June 17, 2013, 06:49:05 pm
Good luck on your MF adventure Erik :)
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: BernardLanguillier on June 17, 2013, 08:45:25 pm
C1 has a lot of good features, but I think it is much less consistent than Lightroom.

For what it is worth, I personally find C1 Pro to consistently deliver a more pleasing rendering with my D800 files.

I would not hesitate a second if I were to use Phaseone H/W.

Cheers,
Bernard
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 18, 2013, 12:23:45 am
Update:

I upgraded to Capture 1 7.1.2 and tested both P45+ Daylight and Flash profiles and they gave identical results.


Hi,

I just posted a preliminary evaluation of color comparing color checker shots, this is for accuracy and not pleasantness.

Little doubt that my Sony Alpha using LR is most accurate (by a wide margin), on P45+ my conversion in LR is somewhat more exact. But I use my own DNG profiles in LR, and have little experience using C1 Pro. Note: I need to update my C1 Pro (I have 7.0).

http://echophoto.dnsalias.net/ekr/index.php/photoarticles/76-my-medium-format-digital-journey?start=4

Outer squares: color rendition of sensor/software, inner squares: reference color without and with brightness correction.
(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Color/ColorPatches.png)
Full size: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Color/ColorPatches.png

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Color/ImatestEvaluation.png)
Full size: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Color/ImatestEvaluation.png

Best regards
Erik

For what it is worth, I personally find C1 Pro to consistently deliver a more pleasing rendering with my D800 files.

I would not hesitate a second if I were to use Phaseone H/W.

Cheers,
Bernard

Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Stefan.Steib on June 18, 2013, 06:46:39 am
Hi Erik

I´m glad I could help a bit.  And I´m sure with this equipment you will be able to do many phantastic images.
I really like the P45+, I had one (thanks to Phase/Espen Beck) for nearly 3 years, and still I think I will buy one for myself soon. This is the tractor of MF, rocksolid, long exposures and 39 Mpix is definitely enough for about anything.
The old V-Blad is a classic, the haptics alone are a reason to use one and the Zeiss lenses are fun and not that expensive anymore.

Greetings from Germany
Stefan
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 18, 2013, 02:24:07 pm
Hi Stefan,

You helped a lot! The viewfinder loupe is a blessing, too!

Best regards
Erik



Hi Erik

I´m glad I could help a bit.  And I´m sure with this equipment you will be able to do many phantastic images.
I really like the P45+, I had one (thanks to Phase/Espen Beck) for nearly 3 years, and still I think I will buy one for myself soon. This is the tractor of MF, rocksolid, long exposures and 39 Mpix is definitely enough for about anything.
The old V-Blad is a classic, the haptics alone are a reason to use one and the Zeiss lenses are fun and not that expensive anymore.

Greetings from Germany
Stefan
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 19, 2013, 12:44:16 am
Updates 2013-06-19:

Added some samples with artifacts and how C1 and LR handles them, C1 wins.

Added some discussion and samples of DoF (Depth of Field) and diffraction.

Added a pair of samples clearly showing that my P45+ has less dynamic range (DR) than my Sony Alpha 99, although I don't consider this to be an issue. I seldom find DR limiting.

No significant updates expected for a week!

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: torger on June 21, 2013, 07:25:41 am
Great that you finally got an MF system :), buying MF digital second hand has never been better, nowadays one can get good gear to "reasonable" prices. I really like the blog too, I enjoy the "no b*llshit" tech tests :).

Hi,

I got my Hasselblad 555ELD with a P45+ sold by Mr. Rib here on LuLa. I am ver satisfied with what I got.

I started a "blog" describing my experience:

http://echophoto.dnsalias.net/ekr/index.php/photoarticles/76-my-medium-format-digital-journey

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: BernardLanguillier on June 21, 2013, 08:06:29 pm
Updates 2013-06-19:
Added a pair of samples clearly showing that my P45+ has less dynamic range (DR) than my Sony Alpha 99, although I don't consider this to be an issue. I seldom find DR limiting.

Are you absolutely, beyond any possible doubt, certain?

Because P45+ users used to claim that the P45+ had several stops more DR than the best DSLR 4 years ago, the D3x, that itself clearly has better DR than your Sony.

Either you or them must be wrong. ;)

Cheers,
Bernard
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 21, 2013, 11:12:19 pm
Hi,

The comparison I made was using Lightroom, also it was at actual pixels. I will revisit the issue when I am back from travel. Will retest with Capture One, too. The Sony I have has the same sensor as the Nikon D600.

Best regards
Erik


Are you absolutely, beyond any possible doubt, certain?

Because P45+ users used to claim that the P45+ had several stops more DR than the best DSLR 4 years ago, the D3x, that itself clearly has better DR than your Sony.

Either you or them must be wrong. ;)

Cheers,
Bernard

Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: yaya on June 22, 2013, 03:18:55 am
I will revisit the issue when I am back from travel. Will retest with Capture One, too.

I vote for more travel and less testing  ;)
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: jerome_m on June 22, 2013, 04:12:44 am
More travel and less testing may be good, but trying to understand one's camera capabilities is also a must.

About dynamic range, you published the following curves:

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/DynamicRange/RawAnalyzer_P45.png)

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/DynamicRange/SonyAlpha_99_raw_analyzer.png)

I'll use the red channel as an example, because it is not clipped. The histogram goes between +2 and -8 for the P45 and between +1.5 and -8 or -5 (depending how one interprets the artifacts) on the A99. I understand that the artifacts (the fact that the histogram lacks values) appear faster on the A99 because it uses less quantization bits. But why are the histograms so different?
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: BernardLanguillier on June 22, 2013, 04:33:09 am
Hi,

The comparison I made was using Lightroom, also it was at actual pixels. I will revisit the issue when I am back from travel. Will retest with Capture One, too. The Sony I have has the same sensor as the Nikon D600.

Ah yes, I haf forgotten that you had replaced your A900, it makes more sense now.

Cheers,
Bernard
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: EricWHiss on June 22, 2013, 04:35:09 am
The measurement of DR is almost always controversial and the value useful to photographers is not the ISO defined version.  I recommend you try shooting a transmission step wedge and using imatest software to get data more reliable than comparing histograms.
 
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 22, 2013, 06:36:20 am
Hi,

I will do that pretty soon, but I wanted to see it from a more practical side, namely, how smooth deep shadow detail I can extract from an ETTR image. This was a side effect of some other testing I have made

Shooting a wedge under identical conditions will give interesting results. On the other hand that is exactly what DxO-mark, but they use a test target developed for analyzing dynamic range, so I assume I would just confirm their data.

Best regards
Erik


The measurement of DR is almost always controversial and the value useful to photographers is not the ISO defined version.  I recommend you try shooting a transmission step wedge and using imatest software to get data more reliable than comparing histograms.
 
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 22, 2013, 08:58:58 am
Hi,

The Hassy is not with me on the trip, I carry the Sony as I shot some birds and also some video. There are limits to weight...

I plan to have the Hassy on a trip to Dolomites later this year.

Testing is good to find out how to make best use of your stuff. A wasted test shot is much better than a missed opportunity.

Best regards
Erik

I vote for more travel and less testing  ;)
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 22, 2013, 09:23:22 am
Hi,

This are my present plans for testing...

I have been asked to shoot some long exposures and post raw images.

I will be on business travel and hope to sneak in some interesting shooting.

I will probably shoot a comparison between 24MP APS-C, 24 MP full frame and 39 MP MFD.

Stuffer wedge shots in a week or so. Shooting the wedge is quite demanding as you need to eliminate all light leaks.

Focusing accuracy with waist level viewfinder vs. Loupe finder.

MLU vs. No MLU

Hopefully, there will be about an even split between test shooting and real images.

Hopefully, I can also look into using C1 as an alternative to Lightroom.

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 22, 2013, 09:48:23 am
Hi,

The reason I show the raw data is to indicate how far we are of ETTR. Note also that I use a logarithmic Y axis. The way I look at this I see the luminosity range of a channel from ETTR exposure down to say 500 pixels. I presume that low contributions are more coming from noise than pixels. What I think the raw images show is that both images are reasonably close to ETTR. Than I look at how much shadow details I can extract, and what amount of noise I get.

Best regards
Erik

More travel and less testing may be good, but trying to understand one's camera capabilities is also a must.

About dynamic range, you published the following curves:

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/DynamicRange/RawAnalyzer_P45.png)

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/DynamicRange/SonyAlpha_99_raw_analyzer.png)

I'll use the red channel as an example, because it is not clipped. The histogram goes between +2 and -8 for the P45 and between +1.5 and -8 or -5 (depending how one interprets the artifacts) on the A99. I understand that the artifacts (the fact that the histogram lacks values) appear faster on the A99 because it uses less quantization bits. But why are the histograms so different?
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: jerome_m on June 22, 2013, 01:01:15 pm
I noticed the logarithmic Y axis. It explains why we have "combs" in the lower part of the signal.

Still, it seems reasonable to think that the actual image data is represented by the envelope of the histogram. That envelope goes to lower values on the P45+ than on the Sony.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 22, 2013, 01:56:58 pm
Yeah,

Question is how much is fake and how much is real. What I can see is that I tried to lift some shadow detail, and that detail is smooth in the Alpha 99 image but has a lot of noise in the P45+ image. Now, it could be that the lens on the Sony has more vailing flare, making shadow smoother, or something else. As exposure is pretty much ETTR I would expect that the image having better DR would have cleaner shadows.

Just to make clear, noise would distribute the signal over many values. Say that lowest real signal would correspond to the data number of 16 and we have a readout noise of 16 electrons, that would spread the signal down to perhaps 5. My guess is is that readout noise on the P45 sensor is about 16. Phase One gives a DR of 12 EV in the spec sheet. So their data says that dynamic range goes from +3EV to -9EV as +3EV represents saturation.

The "comb shape" of the histogram is an artifact of the histogram and not the sensor data. The histogram bunches data in 32 wide channels, but shows the channels with fixed with.

Best regards
Erik

I noticed the logarithmic Y axis. It explains why we have "combs" in the lower part of the signal.

Still, it seems reasonable to think that the actual image data is represented by the envelope of the histogram. That envelope goes to lower values on the P45+ than on the Sony.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 24, 2013, 06:39:28 pm
Some updates:

1) Comment on shadow/dark detail being less noisy on Capture One than LR4 added (needs to be investigated

2) Real worlds samples added

3) Format comparison added (P45+, full frame 24MP and 24 MP APS-C). Somewhat perplexing results, needs more checking.

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Doug Peterson on June 24, 2013, 08:38:10 pm
All these lab tests really hurt my head.

I'd really encourage you to use more tests like the one you did at the top of the Dynamic Range page. But I'd suggest including Capture One - it's not coincidence that the overwhelming majority of the users on this forum and GetDPI who are asked where to process Phase One files say "Capture One".

And don't be constrained to default settings in the software either. Feel free to tweak noise reduction and sharpening on both images to make each one sing as best as you can for your aesthetic - that's the way you'd use the camera in real life, why do any differently in the tests. There is some ostensible academic value in isolating the variables, but there is little practical value in it.

In particular the color tests you've done don't really correlate to creative image making. Such delta-e color accuracy charting is of great value for art reproduction. But the flash and daylite profiles in Capture One aren't meant for art reproduction. They are meant to balance accuracy and pleasantness of color. If you wanted to minimize delta-e believe me you could hit some insanely tight performance requirements (our Department of Cultural Heritage does it all the time as measured by FADGI and METAMORFOZE compliance (http://www.dtdch.com/page/fadgi-image-performance-report)). But this won't necessarily make your pictures prettier (better than even odds in my experience that it won't). The Colorchecker Passport is a nice consumer-grade profiling system but
1) it's usually brought up in conversation when the default LR profile is pretty awful as it is in this case for the P45+
2) it increases accuracy, but with no human touch to the pursuit of making pleasant color (as is the case when the color gurus at Capture One sit down and tweak profiles for dozens of hours per back to really make the color sing in as broad of situations as is possible)
3) it isn't nearly as accurate as a more professional profiling system (more patches, more constraints on production, more fine tuning steps)

I really think you're limiting yourself using LightRoom. The dark frame data isn't used (important for deep shadow recovery and long exposures), the algorithms aren't as deeply catered for this back, and the overall math is, IMO, behind C1 for image quality.

Same thing with Raw Analyzer. It's not going to use the dark frame data to bring as much life/accuracy to the shadows as C1 will. Academically interesting, but not very relevant to how far into the shadows you can get printable/pleasant shadows.

Still always nice to see a digital back based on a sensor from 2005 take on a dSLR from late 2012 and hold it's own even in third party software.

And all that said, thanks for sharing your results. I know how inherently imperfect, frustrating, and criticism all testing is. Thank you very much for doing the enormous work of doing your tests and sharing the results.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: BernardLanguillier on June 24, 2013, 09:05:48 pm
Still always nice to see a digital back based on a sensor from 2005 take on a dSLR from late 2012 and hold it's own even in third party software.

Yep, it can be assumed that the top contenders on both sides are a bit better than that, but DR is pretty much an issue of the past, unless you are invested in Canon lenses.  ;)

http://www.dxomark.com/index.php/Cameras/Compare-Camera-Sensors/Compare-cameras-side-by-side/(appareil1)/831%7C0/(brand)/Sony/(appareil2)/792%7C0/(brand2)/Nikon/(appareil3)/746%7C0/(brand3)/Phase%20One

Cheers,
Bernard
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 24, 2013, 11:46:38 pm
Hi,

Capture 1: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Castle2/20130624-CF043185_C1.jpg

LR 4.4: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Castle2/20130624-CF043185.jpg

Raw image: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Castle2/RawImages/20130624-CF043185.iiq

I own both Capture 1 and Lightroom, but Lightroom has been my main tool since 2006. So I do some testing with Capture 1 but I'm not really comfortable with it and workflow matters a lot.

I have actually seen that C1 gives cleaner shadows, and will add some C1 processed images later on, like end of this week.

Personally, I never shoot people, so skin reproduction plays little role for me.

The reason I use Raw Analyser is mainly that it shows me the raw data. With Raw Analyser I can see how near I am saturation on each channel far more reliably than looking at histograms on the back or histograms in LR or C1. The histograms in LR 4 (PV 2012) hide clipping. So if we look at the DR tests the Raw analyser tells me that:

- The P45+ image is near saturation, has some clipped pixels.
- The Sony image could take 0.5 stop more exposure
- The scene illumination range is around 11EV, both P45+ and Sony image have very few pixels below -8EV and both go to +3EV. So exposure is nearly optimal for highlights.

Finally, I am not really doing tests. For me it is about learning my equipment. Each time I get something new I put it trough a lot of tests. It is a good way to learn.

Best regards
Erik



All these lab tests really hurt my head.

I'd really encourage you to use more tests like the one you did at the top of the Dynamic Range page. But I'd suggest including Capture One - it's not coincidence that the overwhelming majority of the users on this forum and GetDPI who are asked where to process Phase One files say "Capture One".

And don't be constrained to default settings in the software either. Feel free to tweak noise reduction and sharpening on both images to make each one sing as best as you can for your aesthetic - that's the way you'd use the camera in real life, why do any differently in the tests. There is some ostensible academic value in isolating the variables, but there is little practical value in it.

In particular the color tests you've done don't really correlate to creative image making. Such delta-e color accuracy charting is of great value for art reproduction. But the flash and daylite profiles in Capture One aren't meant for art reproduction. They are meant to balance accuracy and pleasantness of color. If you wanted to minimize delta-e believe me you could hit some insanely tight performance requirements (our Department of Cultural Heritage does it all the time as measured by FADGI and METAMORFOZE compliance (http://www.dtdch.com/page/fadgi-image-performance-report)). But this won't necessarily make your pictures prettier (better than even odds in my experience that it won't). The Colorchecker Passport is a nice consumer-grade profiling system but
1) it's usually brought up in conversation when the default LR profile is pretty awful as it is in this case for the P45+
2) it increases accuracy, but with no human touch to the pursuit of making pleasant color (as is the case when the color gurus at Capture One sit down and tweak profiles for dozens of hours per back to really make the color sing in as broad of situations as is possible)
3) it isn't nearly as accurate as a more professional profiling system (more patches, more constraints on production, more fine tuning steps)

I really think you're limiting yourself using LightRoom. The dark frame data isn't used (important for deep shadow recovery and long exposures), the algorithms aren't as deeply catered for this back, and the overall math is, IMO, behind C1 for image quality.

Same thing with Raw Analyzer. It's not going to use the dark frame data to bring as much life/accuracy to the shadows as C1 will. Academically interesting, but not very relevant to how far into the shadows you can get printable/pleasant shadows.

Still always nice to see a digital back based on a sensor from 2005 take on a dSLR from late 2012 and hold it's own even in third party software.

And all that said, thanks for sharing your results. I know how inherently imperfect, frustrating, and criticism all testing is. Thank you very much for doing the enormous work of doing your tests and sharing the results.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 25, 2013, 12:44:09 am
Hi,

I am not concerned so much about DR, it is seldom a problem for me, less than one promille of my images are DR-limited, I guess.

Doug is quite right about the KAF sensor from 2006 being impressive, the problem is that we have see so little development, see below.

On the other hand, DxO data indicates that my Sony Alpha 99 has about 1EV more DR than the P45+ and about 0.5EV more than the quite recent IQ 180. The data for the IQ180 and the P45+ essentially overlap, but the IQ 180 goes down 29 ISO and gains advantage over the P45+.

Best regards
Erik


Yep, it can be assumed that the top contenders on both sides are a bit better than that, but DR is pretty much an issue of the past, unless you are invested in Canon lenses.  ;)

http://www.dxomark.com/index.php/Cameras/Compare-Camera-Sensors/Compare-cameras-side-by-side/(appareil1)/831%7C0/(brand)/Sony/(appareil2)/792%7C0/(brand2)/Nikon/(appareil3)/746%7C0/(brand3)/Phase%20One

Cheers,
Bernard

Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: design_freak on June 25, 2013, 06:12:03 am
I vote for more travel and less testing  ;)
+1000
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 25, 2013, 02:20:09 pm
Hi,

Testing and shooting is a great way to learn about your system. Learn handling, find issues and learn to handle pecularities. For instance, moving from FF DSLR to MFDB raises a new challenge in that depth of field is shorter. Testing is a good way to learn living with the reduced depth of field. It is nice to work out one shooting technique and make early mistakes at home than learning by doing on travel and missing opportunities.

Yeasterday, I ruined one of my shots by not stopping down to optimal aperture on of one of my lenses. I wanted a short DoF, and ended up with a useless picture. Lesson learned. Today I shot a similar subject with two lenses (120/4 and 150/4), so next time I will know more about how they perform and can make an educated choice.

Admittedly, I am also quite curious, coming with my background as a engineer and science student.

Best regards
Erik

+1000
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: jerome_m on June 25, 2013, 03:44:59 pm
In particular the color tests you've done don't really correlate to creative image making. Such delta-e color accuracy charting is of great value for art reproduction. But the flash and daylite profiles in Capture One aren't meant for art reproduction. They are meant to balance accuracy and pleasantness of color. If you wanted to minimize delta-e believe me you could hit some insanely tight performance requirements (our Department of Cultural Heritage does it all the time as measured by FADGI and METAMORFOZE compliance (http://www.dtdch.com/page/fadgi-image-performance-report)). But this won't necessarily make your pictures prettier (better than even odds in my experience that it won't). The Colorchecker Passport is a nice consumer-grade profiling system but
1) it's usually brought up in conversation when the default LR profile is pretty awful as it is in this case for the P45+
2) it increases accuracy, but with no human touch to the pursuit of making pleasant color (as is the case when the color gurus at Capture One sit down and tweak profiles for dozens of hours per back to really make the color sing in as broad of situations as is possible)
3) it isn't nearly as accurate as a more professional profiling system (more patches, more constraints on production, more fine tuning steps)

I am citing this post because it should not go unnoticed.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Guy Mancuso on June 25, 2013, 04:41:35 pm
Erik

Couple quick notes the P45plus is a older back with pretty much a outdated sensor comparing it to the new breeds of the Dalsa lets say and even your new Sony and Nikons. So the DR will probably will not be as wide open lets say as the newer sensors thats a given as I tested this a long time ago with the P65 Plus and P40 Plus. It still is a great sensor and it does have that Kodak color and saturation that it is known for compared to the Dalsa which has more DR and a more neutral color palette. Not that one is better than the other but there is a difference and some folks like one over the other for sure. I had the P25, P30 Plus backs and used the P45plus back pretty often. They are pretty much the same Kodak breeds of sensors but than I moved on to the Dalsa via the P40, IQ 160 and IQ 140 which I liked better but that is my preference in the end was the Dalsa. What the P45 plus is good at is very long exposures good ISO noise levels up to maybe ISO 200 but after that shadow noise will come into play with the higher ISO's. So if you use it within its limitations its a great back. Use it outside of them you may have some disappointment. But I encourage you to use C1 as in the past Lightroom sucked on those backs, not sure about today and there newer versions since I dont even have it on my machine anymore. But if I am bias than C1 is my raw processing machine and I use that on every cam it supports or i wont buy a system it does not support. You will get better results that I can tell you as the Phase engineers specifically work C1 for there backs which makes perfect sense.

BTW I was passing by and glad to see you finally jumped in. MF is fun and the results are worth it IMHO. Also go have some fun, testing gets pretty damn boring even for a engineer. Be well
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 25, 2013, 06:16:30 pm
Guy,

Thanks for chiming in, always nice to hear from you ;-)

Just a few observations...

I'm not really interested in high ISO work. Almost anything I shoot I always use base ISO.

Regarding C1 and LR4, the way it is I am pretty much aligned to LR4, not because it is best but because I haved used it since 2006 and also because I am much into parametric workflow. I have bought C1 some time ago, and I am using it in parallell.

I am aware that P45+ is an older sensor and also that it uses a Kodak sensor.



Erik

Couple quick notes the P45plus is a older back with pretty much a outdated sensor comparing it to the new breeds of the Dalsa lets say and even your new Sony and Nikons. So the DR will probably will not be as wide open lets say as the newer sensors thats a given as I tested this a long time ago with the P65 Plus and P40 Plus. It still is a great sensor and it does have that Kodak color and saturation that it is known for compared to the Dalsa which has more DR and a more neutral color palette. Not that one is better than the other but there is a difference and some folks like one over the other for sure. I had the P25, P30 Plus backs and used the P45plus back pretty often. They are pretty much the same Kodak breeds of sensors but than I moved on to the Dalsa via the P40, IQ 160 and IQ 140 which I liked better but that is my preference in the end was the Dalsa. What the P45 plus is good at is very long exposures good ISO noise levels up to maybe ISO 200 but after that shadow noise will come into play with the higher ISO's. So if you use it within its limitations its a great back. Use it outside of them you may have some disappointment. But I encourage you to use C1 as in the past Lightroom sucked on those backs, not sure about today and there newer versions since I dont even have it on my machine anymore. But if I am bias than C1 is my raw processing machine and I use that on every cam it supports or i wont buy a system it does not support. You will get better results that I can tell you as the Phase engineers specifically work C1 for there backs which makes perfect sense.

BTW I was passing by and glad to see you finally jumped in. MF is fun and the results are worth it IMHO. Also go have some fun, testing gets pretty damn boring even for a engineer. Be well
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 25, 2013, 06:38:00 pm
Hi,

I think those are valid points. I know that Doug works with color reproduction at DT, or at least DT has a division working in that area.

Doug is probably right in some aspects. On the other hand I would guess that some other experts, like Jeff Schewe may have other opinions, but Jeff is working with an other company making imaging software. Jeff suggests that noise reduction and tone mapping functions in Lightroom are superior to Capture 1: http://www.luminous-landscape.com/forum/index.php?topic=79446.msg640785#msg640785

I would still suggest that reproducing a color checker is a good thing. It is the closest thing to a reference available to everyone. It is an old stalwart of the industry.

I also think that color profiling in LR is working differently than the impression Doug has. As far as I know, each new sensor is measured with a monochromator at some lab working for Adobe. When you build a DNG profile you are tweaking the original profile. So it still based on monochromator data but individually tuned.

Best regards
Erik
 


Quote
In particular the color tests you've done don't really correlate to creative image making. Such delta-e color accuracy charting is of great value for art reproduction. But the flash and daylite profiles in Capture One aren't meant for art reproduction. They are meant to balance accuracy and pleasantness of color. If you wanted to minimize delta-e believe me you could hit some insanely tight performance requirements (our Department of Cultural Heritage does it all the time as measured by FADGI and METAMORFOZE compliance). But this won't necessarily make your pictures prettier (better than even odds in my experience that it won't). The Colorchecker Passport is a nice consumer-grade profiling system but
1) it's usually brought up in conversation when the default LR profile is pretty awful as it is in this case for the P45+
2) it increases accuracy, but with no human touch to the pursuit of making pleasant color (as is the case when the color gurus at Capture One sit down and tweak profiles for dozens of hours per back to really make the color sing in as broad of situations as is possible)
3) it isn't nearly as accurate as a more professional profiling system (more patches, more constraints on production, more fine tuning steps)


I am citing this post because it should not go unnoticed.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: yaya on June 26, 2013, 01:49:04 am
Hi,

I think those are valid points. I know that Doug works with color reproduction at DT, or at least DT has a division working in that area.

Doug is probably right in some aspects. On the other hand I would guess that some other experts, like Jeff Schewe may have other opinions, but Jeff is working with an other company making imaging software. Jeff suggests that noise reduction and tone mapping functions in Lightroom are superior to Capture 1: http://www.luminous-landscape.com/forum/index.php?topic=79446.msg640785#msg640785

I would still suggest that reproducing a color checker is a good thing. It is the closest thing to a reference available to everyone. It is an old stalwart of the industry.

I also think that color profiling in LR is working differently than the impression Doug has. As far as I know, each new sensor is measured with a monochromator at some lab working for Adobe. When you build a DNG profile you are tweaking the original profile. So it still based on monochromator data but individually tuned.

Best regards
Erik

Eric Chan might want to chime in and tell you how the profiles for LR are made

As regards colorcheckers etc. the standard one for reproduction is the SG one with far more tones than the 24-patch consumer-grade one. Also when generating profiles one should be using a linear curve and adjust exposure (on the camera) accordingly or otherwise you're compressing the gamut

Yair
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: jerome_m on June 26, 2013, 02:37:43 am
Hi,

I think those are valid points. I know that Doug works with color reproduction at DT, or at least DT has a division working in that area.

Doug is probably right in some aspects. On the other hand I would guess that some other experts, like Jeff Schewe may have other opinions, but Jeff is working with an other company making imaging software. Jeff suggests that noise reduction and tone mapping functions in Lightroom are superior to Capture 1: http://www.luminous-landscape.com/forum/index.php?topic=79446.msg640785#msg640785

I would still suggest that reproducing a color checker is a good thing. It is the closest thing to a reference available to everyone. It is an old stalwart of the industry.

I also think that color profiling in LR is working differently than the impression Doug has. As far as I know, each new sensor is measured with a monochromator at some lab working for Adobe. When you build a DNG profile you are tweaking the original profile. So it still based on monochromator data but individually tuned.

Measuring a sensor with a monochromator is not difficult and would give direct information about the primary filters. It should be the preferred method.

But this is not what Doug said. Doug believes that accurate color reproduction is not what the manufacturers are aiming to. This is also my opinion. And if the manufacturers are not designing their back for accurate color reproduction, measuring the accuracy of color reproduction is futile.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: torger on June 26, 2013, 04:02:20 am
Measuring a sensor with a monochromator is not difficult and would give direct information about the primary filters. It should be the preferred method.

But this is not what Doug said. Doug believes that accurate color reproduction is not what the manufacturers are aiming to. This is also my opinion. And if the manufacturers are not designing their back for accurate color reproduction, measuring the accuracy of color reproduction is futile.

The possibility to produce accurate color is bound to the sensor response. Final image color output is much bound to software, ie capture one and its profiles (or phocus/hasselblad and their natural color system). I don't know how much influence the back manufacturers have on bayer filter array design, I'd guess more for the newer exclusive sensors than what it was back for the P45+, for the KAF39000 I would guess the digital back manufacturers was not involved at all in sensor design (?). I'd guess Phase One has more influence on sensor design than Hasselblad has.

Anyway if you just can get the raw data you can tune the color any way the bayer array filters allows. As far as I know DxOmark measures raw data response in their color tests, ie they don't use any manufacturer provided raw converter and profiles, so they measure the sensor's ability to reproduce accurate color in some standard lighting condition, not the color you'll get if you use the manufacturer provided raw software and default profiles.

What's important is the sensor's ability to differ between nearby/similar colors, which DxOmark does measure. As long as it can do that you can tune the color in any direction you want and different colors will still be different colors. If similar colors are registered with the same RGB raw values no profile in the world can make them differ.

For me that aspect is a key performance indicator of a sensor. It's a bit difficult to evaluate though if you just get a single metric, as the sensor may be bad at separating greens but good at separating skin color, and thus may produce better results for you than a sensor good at greens but slightly less good at skin color, if your main subject is skin. A landscape photographer may prefer the sensor that is better at separating greens.

Color separation is reduced in the shadows, and I'm not sure about this but it seems to me that it's a bit separate from dynamic range, ie you can measure quite good dynamic range but still lose more color separation than another sensor which on paper has worse dynamic range. Some sensors get quite monochromatic in the shadows (usually towards green) before noise gets too bad.

To summarize, what we should be interested in and measure is "color separation" rather than "color accuracy". Different colors registered separately can be tuned, different colors registered as a single color cannot. In technical terms we want a "low metameric error". In general terms the Dalsa sensors have lower metameric error than the Kodaks, but I don't know how performance is in specific color ranges.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 26, 2013, 04:38:56 am
Hi,

Interestingly DT (the company Doug works for) also refers to this document: http://www.dtdch.com/page/fadgi-image-performance-report

As I recall they have a DeltaE avg of 2.0 (or so)
Erik
Best regards


Measuring a sensor with a monochromator is not difficult and would give direct information about the primary filters. It should be the preferred method.

But this is not what Doug said. Doug believes that accurate color reproduction is not what the manufacturers are aiming to. This is also my opinion. And if the manufacturers are not designing their back for accurate color reproduction, measuring the accuracy of color reproduction is futile.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: jerome_m on June 26, 2013, 04:48:54 am
It seems to me that people on this thread are trying to reinvent the wheel. Quite a lot has been written on the subject of color reproduction accuracy in the context of document digitization. Reading books and standards on the subject would seem the thing to do first.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 26, 2013, 05:41:22 am
Hi,

Just a short comment on metameric error. If you refer to the one used by DxO it is essentially based on Delta E measured on the 16 color fields of the color checker.

It is described here: http://www.dxomark.com/index.php/About/In-depth-measurements/Measurements/Color-sensitivity

According to Tim Perkin, there is a good correlation between the SMI and his color preferens, that is high SMI -> good colors.

P45+ -> 72
Pentax 645D -> 75
Nikon D800 -> 78
IQ180 -> 80
Sony Alpha 99 -> 85
Sony Alpha 900 -> 87

Best regards
Erik





Hi,

Interestingly DT (the company Doug works for) also refers to this document: http://www.dtdch.com/page/fadgi-image-performance-report

As I recall they have a DeltaE avg of 2.0 (or so)
Erik
Best regards


Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: torger on June 26, 2013, 06:28:03 am
According to Tim Parkin, there is a good correlation between the SMI and his color preferens, that is high SMI -> good colors.

Tim is a landscape photographer and as far as I know works very actively with colors, ie tuning individually per image in Photoshop. What you need then is a malleable raw file, ie good color separation (low metameric error, which leads to high SMI). What the colors actually are out of the box is less important. So I'm not surprised there is a good correlation.

I would not trust it that much though, I had a Canon 7D (APS-C) which I think did not have that malleable files, but it still has 78. I would guess part of the problem is that DR is not factored in, ie poor color accuracy in darker colors won't show in the SMI. Looking at the DxO charts the P45+ has less noise covariance in dark colors than that 7D, despite lower SMI. Modern Sony cameras excel in DR too though, which contributes to the malleability. The 7D has apart from quite low DR really bad banding noise further reducing subjective DR.

As far as I understand the MFD has mainly gained its color reproduction reputation from the default settings in the manufacturer-provided raw converter, and then mainly looking at skin color in studio flash photography, as humans are most sensitive to skin, and studio flash photography is a much more common(?) use case for MFD than for example landscape photography. If you work very actively with color in your files and don't depend so much on the provided tools the raw sensor performance means more and tuned defaults less.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Doug Peterson on June 26, 2013, 09:49:16 am
Doug believes that accurate color reproduction is not what the manufacturers are aiming to. This is also my opinion. And if the manufacturers are not designing their back for accurate color reproduction, measuring the accuracy of color reproduction is futile.

This is in fact not what I said.

I said "But the flash and daylite profiles in Capture One aren't meant for art reproduction. They are meant to balance accuracy and pleasantness of color."

The design of the digital back is almost exclusively geared towards producing excellent image quality, including color. They design the back to provide incredibly good raw files for everything from fashion to product to art reproduction.

The ability for an IQ180 to distinguish between extremely subtle color variation has been noted by many users here and on other forums. The ability for an IQ180 to accurately show the transition from a strongly saturated deep shadow to a strongly saturated hot highlight has been likewise noted. We've noticed this improved even further with the IQ2 generation (see this test of the IQ260 vs P45+ (https://digitaltransitions.com/blog/dt-blog/iq260-vs-p45-long-exposure) for instance).

The default profiles in Capture One are good for art reproduction, but they aren't perfect. They must, inherently, provide some accommodations to ensure that the back produces pleasant color in a variety of situations (fashion/weddings/portrait/landscape/architecture/product/etc).

Since the back has an excellent sensor, and the software allows for both arbitrary-ICC input (meaning you can generate a profile out of any standards-based profiling software) and a really excellent ICC-editor (Color Editor) it's really very easy (with the proper expertise) to generate a profile for Cultural Heritage or Art Repro situations which exceeds the strictest international guidelines for color accuracy in preservation environments. Again, this is not theoretical; we do this as routine business with our Cultural Heritage clients (http://www.dtdch.com/page/clients).

You'll get pretty close for art repro purposes using the default flash profile and high quality flash illumination. But you'll do better with a profile geared exclusively for art reproduction. Which is easy to do yourself if you have a background in profile creation, or if you work with a value added partner like us.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: jerome_m on June 26, 2013, 05:14:37 pm
This is in fact not what I said.

Indeed it isn't and you did talk about specific profiles. My apologies.

Now, allow me a question. ISO 17321 specifies a way to measure a metameric index. Some MF backs are relatively low on that metric, compared to other cameras with a smaller sensor. Wouldn't that mean that their sensor will be less capable of accurate color than these other cameras, even with a perfectly tuned profile?
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Doug Peterson on June 26, 2013, 05:47:05 pm
Indeed it isn't and you did talk about specific profiles. My apologies.

Now, allow me a question. ISO 17321 specifies a way to measure a metameric index. Some MF backs are relatively low on that metric, compared to other cameras with a smaller sensor. Wouldn't that mean that their sensor will be less capable of accurate color than these other cameras, even with a perfectly tuned profile?

I'd be glad for references (feel free to email me) regarding this information (who did the testing, under what conditions, which backs are being described etc).

But in general I prefer to examine real world testing. In nearly every image quality category a numerical representation of performance fails to fully describe the strengths/weaknesses of a given system. For instance dynamic range can ostensibly reduced to a single number for direct comparison between two systems, but in reality I've found you must consider a variety of factors like what kind of noise is created (is it pretty or ugly, uniform or clumpy) and whether color is consistent along quarter tone transitions and highlights (especially important for portraits in high contrast light among other things). The result is that two cameras which are (carefully and honestly) measured as having the same numerical dynamic range have very different abilities to reach into highlights/shadows and pull out photographically useful and aesthetically pleasant image content. So it's just so much more meaningful to take and compare actual pictures.

In my real world experience with profiling many kinds of cameras and working with those profiled cameras with some very demanding clients (http://www.dtdch.com/page/clients) to capture real world objects I can say quite confidently the modern Phase One backs are exceptional at this work.

I would be glad to explore with you the underlying mechanics of this real world performance vis a vis metameric index measurement. But it would be purely an academic conversation. Feel free to email me.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 27, 2013, 12:35:45 am
Hi,

This is discussed in the DxO-mark article here: http://www.dxomark.com/index.php/About/In-depth-measurements/Measurements/Color-sensitivity.

So the measurement is based on the 18 color fields of the Color Checker. Leaves a few questions. One is that I don't think it can be based on unprocessed raw data, so color conversion matrix is involved.

A note is that of all cameras I have checked the Sony Alpha 900 is on top regarding SMI, and that camera is said to have very good color by some authors. The IQ180 has high SMI while the P45+ has quite low SMI.

As a side issue, Miles Hecker posted samples from Pentax 645D (low SMI) and Nikon D3X (high SMI) where I think both he and I preferred the Pentax rendition.

I will post some samples from Sony Alpha 99 and P45+ tonight or tomorrow, those are real world shots and I tried to process the image in both C1 and LR.


Best regards
Erik


I'd be glad for references (feel free to email me) regarding this information (who did the testing, under what conditions, which backs are being described etc).

But in general I prefer to examine real world testing. In nearly every image quality category a numerical representation of performance fails to fully describe the strengths/weaknesses of a given system. For instance dynamic range can ostensibly reduced to a single number for direct comparison between two systems, but in reality I've found you must consider a variety of factors like what kind of noise is created (is it pretty or ugly, uniform or clumpy) and whether color is consistent along quarter tone transitions and highlights (especially important for portraits in high contrast light among other things). The result is that two cameras which are (carefully and honestly) measured as having the same numerical dynamic range have very different abilities to reach into highlights/shadows and pull out photographically useful and aesthetically pleasant image content. So it's just so much more meaningful to take and compare actual pictures.

In my real world experience with profiling many kinds of cameras and working with those profiled cameras with some very demanding clients (http://www.dtdch.com/page/clients) to capture real world objects I can say quite confidently the modern Phase One backs are exceptional at this work.

I would be glad to explore with you the underlying mechanics of this real world performance vis a vis metameric index measurement. But it would be purely an academic conversation. Feel free to email me.
Title: Some more samples
Post by: ErikKaffehr on June 27, 2013, 01:04:25 am
Hi,

Here are some samples I shot yesterday and processed Quick & Dirty:

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Forsmark/20130626-CF043214_small.jpg)
Above: P45+ processed in LR4.4. Full size: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Forsmark/20130626-CF043214.jpg
(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Forsmark/20130626-CF043215_C1_small.jpg)
Above: P45+ processed in C1. Full size: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Forsmark/20130626-CF043214_C1.jpg
(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Forsmark/20130626-_DSC2169_small.jpg)
Above: Sony Alpha 99 processed in LR4.4. Full size: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Forsmark/20130626-_DSC2169.jpg

These images are not included in the article yet. C1 is still in the works.

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Forsmark/20130626-CF043218_small.jpg)
P45+ LR4.4 above:
(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Forsmark/20130626-CF043218_C1_small.jpg)
P45+ C1 above:
(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Forsmark/20130626-_DSC2171_small.jpg)
Sony Alpha 99 LR4.4 above:

These images are not included in the article yet. The LR4.4 processed images have gradient filters on water and sky. C1 is still in the works.


Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 28, 2013, 05:19:21 pm
Hi,

I think this samples are impressive, especially the 1:1 crops.

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Stendorren/20130628-CF043276_small.jpg)
(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Stendorren/20130628-CF043276-2.jpg)
(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Stendorren/20130628-CF043276-3.jpg)

Raw data is here: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Stendorren/20130628-CF043276.iiq

Best regards
Erik
Title: Small update: diffraction
Post by: ErikKaffehr on June 29, 2013, 05:37:43 pm
Hi,

I just shot a diffraction series: http://echophoto.dnsalias.net/ekr/index.php/photoarticles/76-my-medium-format-digital-journey?start=11

This is LW/PH MTF 50 for P45+/Sonnar 150 without sharpening at different apertures:

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Diffraction/MTF_of_aperture.png)

In short. Diffraction limit sets in around f/11 and is significant at f/16.

That said, f/22 and f/32 may be OK, but use medium apertures for optimal sharpness.

f/8f/22
(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Diffraction/20130629-CF043302-2.jpg)(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Diffraction/20130629-CF043305-2.jpg)

Best regards
Erik
Title: Another observation: C1 and me, we are no friends...
Post by: ErikKaffehr on June 29, 2013, 05:50:47 pm
Hi,

It has been suggested that Capture One gives superior results to LR4 with Phase One backs. I have tried Capture One and we make no friends. The more I use it the less I like it.

This is just my experience. C1 is a fine product, for sure. It has advantages, like it produces less Moiré and aliasing artefacts and may have a more aggressive sharpening by default.

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Bart_van_der_Wolf on June 29, 2013, 08:31:05 pm
The measurement of DR is almost always controversial and the value useful to photographers is not the ISO defined version.  I recommend you try shooting a transmission step wedge and using imatest software to get data more reliable than comparing histograms.

Hi Eric,

Sorry, but shooting a step-wedge is not more accurate, although may be closer to variable conditions real live shooting situations (partly due to veiling glare), depending on the lens and lighting situation used. For a fair, unbiased review one usually tries to avoid as many variables (such as lens / lighting conditions used) as possible. Ignoring things like these variables is exactly what makes comparisons controversial.

The DxO Mark evaluations seem to be pretty accurate though.

Cheers,
Bart
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Bart_van_der_Wolf on June 29, 2013, 08:34:13 pm
A wasted test shot is much better than a missed opportunity.

Hear, hear.

Chears,
Bart
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Bart_van_der_Wolf on June 29, 2013, 08:43:39 pm
Stouffer wedge shots in a week or so. Shooting the wedge is quite demanding as you need to eliminate all light leaks.

Indeed. it seems so simple, but it requires a lot of preparation and understanding, just like shooting Color profile targets. And even then, I get better (= more accurate) results from shooting multiple uniform area shots (even pairs of shots for elimination of pattern noise).

Cheers,
Bart
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Bart_van_der_Wolf on June 29, 2013, 09:01:02 pm
Question is how much is fake and how much is real. What I can see is that I tried to lift some shadow detail, and that detail is smooth in the Alpha 99 image but has a lot of noise in the P45+ image. Now, it could be that the lens on the Sony has more vailing flare, making shadow smoother, or something else. As exposure is pretty much ETTR I would expect that the image having better DR would have cleaner shadows.

Hi Erik,

Indeed. what one would ideally like to establish is the sensor's capabilities, which leaves the influence of the lens used. in the mix.

Quote
Just to make clear, noise would distribute the signal over many values. Say that lowest real signal would correspond to the data number of 16 and we have a readout noise of 16 electrons, that would spread the signal down to perhaps 5. My guess is is that readout noise on the P45 sensor is about 16. Phase One gives a DR of 12 EV in the spec sheet. So their data says that dynamic range goes from +3EV to -9EV as +3EV represents saturation.

QED! Traditionally the Phase One sensitivity of their sensors has been overstated (as evidenced by the DxO scores), presumably to allow more highlight headroom.

Cheers,
Bart
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 30, 2013, 01:10:29 am
Hi,

Just as a side note, the DxO mark data is an almost exact match for the data given in the data sheet by Kodak.

DR 71.4 dB -> 12 EV
FWC 60000
Readout noise 16 electron charges

FWC/read noise -> 60000 / 16 -> 11.8EV (but all figures are approximate)

Erik

Hi Eric,


The DxO Mark evaluations seem to be pretty accurate though.

Cheers,
Bart
Title: Re: Small update: diffraction
Post by: 32BT on June 30, 2013, 05:02:15 am
Hi,

I just shot a diffraction series:

Erik,

That f22 shot seems to have solved the color-aliasing problems quite nicely, while at the same time the integrity of the luminance signal seems quite intact. Did you try sharpening even more for comparison?
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on June 30, 2013, 10:23:48 am
Quite happy with this image!

First exposure of today's shoot, before setting up anything, all based on experience. Hasselblad 555 ELD, P45+ and 50/4.

(http://echophoto.smugmug.com/Other/Technical/P45/i-j6jXJ5h/0/XL/20130630-CF043307-XL.jpg)
https://maps.google.com/maps?q=58%C2%B038'51%22+N+17%C2%B06'33%22+E&hl=sv&ie=UTF8&ll=58.647498,17.109168&spn=0.005214,0.013443&sll=37.0625,-95.677068&sspn=63.728771,110.126953&t=h&z=17

Best regards
Erik
Title: Some info on lenses added
Post by: ErikKaffehr on July 03, 2013, 01:13:56 am
Hi,

I added some info my lenses.

Sonnar 150/4 very good for distant scenes
Macro Planar shows that it is not intended for distant scenes

Planar 80/2.8 quite OK
Distagon 50/4 quit OK

Best regards
Erik
Title: Comparison with 24MP full frame
Post by: ErikKaffehr on July 03, 2013, 03:35:18 pm
An interesting comparison.

I found that 120/4 Macro Planar worked best for this composition and did a comparison shot with my Sony Alpha 99 SLT using Sony 70-400/4-5.6. macro Planar at f/16 and Sony lens at f/11. Sony image upsized in PS CS5 to same width.

The Sony 24MP smokes the Planar/P45+ in the corners while it may be the other way round at the center?

The Macro Planar 120/4 is the weakest performer I have for the Hassy/P45+, but it was the best match for this composition. I also have a Sonnar 150/4 that is really excellent, but it was to long for this composition. The Macro Planar is not optimized for long distances. It's a macro lens, I am pretty sure it excels in the close up range.


Best regards
Erik
Title: Shadow detail
Post by: ErikKaffehr on July 03, 2013, 11:53:43 pm
Note: I found out that the subject is much less demanding than I originally have thought. The reflections in the water are totally clipped and exposure is essentially on brightest clouds. Shadow goes down to perhaps -6EV, so range is about 9EV.

Here is some hefty shadow detail:


(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/DynamicRange/SDT_1.jpg)
(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/DynamicRange/SDT_2.jpg)

And the whole image:

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/DynamicRange/SDT_3.jpg)

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Stefan.Steib on July 05, 2013, 08:07:46 am
Hi Erik

The Makro planar is a pretty decent performer at infinity. We use the lenskits for the 120mm Hartblei superrotators and
I have compared it to a lot of other lenses.
The point is, you need to focus "exactly" on target. it is not forgiving the slightest mis/front/backfocus .
Same as the 4/40 IF Distagon. It´s a beast and with my Canon´s I normally use LV to get the full resolving power from it.
But that is valid for all VERY SHARP lenses. I would even state that the lesser ones are more forgiving.

Regards
Stefan
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: julienlanoo on July 05, 2013, 10:57:36 am
You re doing what i should have done, Bravo!
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on July 05, 2013, 11:10:03 am
Stefan,

I will retest. I think I have missed focus.

On the other hand, the MTF curves are ugly at infinity but very good at close up range. So what I see is what I expect from the MTF curves. But I was looking at the pictures this morning and decided to retest.

It seems that the 120/4 is one of the lenses I use the most.

Best regards
Erik



Hi Erik

The Makro planar is a pretty decent performer at infinity. We use the lenskits for the 120mm Hartblei superrotators and
I have compared it to a lot of other lenses.
The point is, you need to focus "exactly" on target. it is not forgiving the slightest mis/front/backfocus .
Same as the 4/40 IF Distagon. It´s a beast and with my Canon´s I normally use LV to get the full resolving power from it.
But that is valid for all VERY SHARP lenses. I would even state that the lesser ones are more forgiving.

Regards
Stefan
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on July 05, 2013, 03:29:56 pm
Hi Stefan,

I looked at the images and shot an aperture series also today. I still find that the 120/4 needs to be stopped down a lot at infinity. Today I was using a PM5 prism, I'm trying to get an eyepiece corrected for my vision. I will probably also get a Zeiss Tripler as recommended by Joseph Holmes and Lloyd Chambers. I like the Hartblei loupe, but waist level viewing does not work for me for different reasons. Accurate focusing is an issue, right now, but anyway I find that corners are far worse than center on a decently focused image, at large apertures. Now, I am pretty sure that the problems is field curvature, and that also means that what you focus on will be sharp.

What I see is totally consistent with Zeiss/Hasselblad MTF data.

Best regards
Erik




Hi Erik

The Makro planar is a pretty decent performer at infinity. We use the lenskits for the 120mm Hartblei superrotators and
I have compared it to a lot of other lenses.
The point is, you need to focus "exactly" on target. it is not forgiving the slightest mis/front/backfocus .
Same as the 4/40 IF Distagon. It´s a beast and with my Canon´s I normally use LV to get the full resolving power from it.
But that is valid for all VERY SHARP lenses. I would even state that the lesser ones are more forgiving.

Regards
Stefan
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Stefan.Steib on July 05, 2013, 06:15:39 pm
Hi Eric

yes you need to stop down the 120 Macro, but at best aperture (f11) it is pretty good.
See here:   http://www.dpreview.com/lensreviews/hartblei_120_4_pc_n10/4

The good part of being a bit soft wide open is: it´s perfect for portraits too.

These older lenses were never designed to be used wide open. Totally different philosophy than todays digital lenses.

Regards
Stefan
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on July 06, 2013, 02:09:50 am
Hi Stefan,

I'm normally shooting at f/11-f/16, to gain enough DoF. On the other hand, when I test a lens I am looking for weaknesses and trying to learn how to work around them.

I don't agree with your comments fully.

1) I also arrived at the conclusion that the 120/4 is best used stopped down to f/11 (or even f/16)

2) The Sonnar 150/4 I have is an older lens than the Macro Planar and it is perfectly sharp across the field at f/4, so I don't think that this is a generation issue

3) The simple explanation for the behaviour of the Macro Planar is that it is designed close up work. Field is nearly flat at close distance and curved at infinity. Check Zeiss MTF curves. Ugly at infinity, very nice at 5:1!

4) The curvature of field cause a gradual defocus when you move away from the focused point. What you focus on is sharp. I think I have a pretty nifty demo of that here:
http://echophoto.dnsalias.net/ekr/index.php/photoarticles/74-zeiss-macro-planar-120-on-sony-alpha-99-with-an-arax-tilt-adapter

5) So if you shoot at close distance or repro, the lens would work perfectly fine at any aperture. If you can focus accurately on subject and use selective focus the lens would work fine at any aperture.

6) You can check the MTF data from Zeiss.

7) With selective focus bokeh also plays a role.

The tangential and sagittal curves are quite close which indicates that both astigmatism and lateral chromatic aberration is well corrected. The curves at infinity are very bad. The probable cause is that the focal plane is curved. But if you look at the second set of curves at close up range the curves are very good.

Regarding the Distagon 40, it seems that there are at least three generations. The original 40/4, the 40/4 CF (FLE) and the latest 40/4 FLE IF. The FLE adds a floating group which corrects for field curvature. The FLE control is implemented as an extra focusing ring. The FLE IF is a newer design with internal focus.

The DPReview article you refer to tests then Planar on a 24x36 sensor, but I am shooting on a P45+ which covers a much larger area causing the field curvature being a much more  significant problem. When I shot my 120/4 on the Sony Alpha 99 I have seen less issue with field curvature and I could focus wherever I wanted, exactly, using LV manual focus.

To sum up, I use the Planar 120/4 macro extensively, but I need to stop down more than the other lenses I have.

I have shot a diffraction series on Sonnar 150/4 (see below), that lens performed best at f/5.6 and there was a significant drop of at f/16. But I still think that shooting at f/16 is OK and it is often needed for DOF.

[img]http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Samples/Diffraction/MTF_of_aperture.png[/png]

Sorry for responding so long, but I guess that this discussion may be of some interest to potential buyers.

Best regards
Erik

Hi Eric

yes you need to stop down the 120 Macro, but at best aperture (f11) it is pretty good.
See here:   http://www.dpreview.com/lensreviews/hartblei_120_4_pc_n10/4

The good part of being a bit soft wide open is: it´s perfect for portraits too.

These older lenses were never designed to be used wide open. Totally different philosophy than todays digital lenses.

Regards
Stefan
Title: A comparison...
Post by: ErikKaffehr on July 06, 2013, 02:40:05 am
Hi,

The enclosed image was shot at f/11 (I think as I have no EXIF data) with the Planar 120/4. I think it is decently focused as it was a part of an aperture series and the f/4 image still has decent focus. The other image was shot with Sony Alpha 99 and a SAL 70-400/4-4.5G lens at f/8. The Sony image was uprezzed to the same width as the Hasselblad/Planar image using bicubic.

Hasselblad to the left Sony to the right, actual pixels.

Same camera position, light was changing a bit.

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Chris Livsey on July 06, 2013, 03:29:53 am
I will probably also get a Zeiss Tripler as recommended by Joseph Holmes and Lloyd Chambers. I like the Hartblei loupe, but waist level viewing does not work for me for different reasons.

Erik, I have a Hartblei loupe (500c/m P20 back) and find it makes a huge difference to my focus ability. I was brought up on the reverse view so it is second nature but I can see why it would trouble others. I am curious as to why you would go from the 4x down to 3x? You will gain the comfort of 'correct" viewing but loose the extra magnification an interesting compromise the outcome is awaited with interest.

 I'm a Makro Planar fan as well and would be interested in how the highly praised H series 100mm and the 120 H Macro, of which I hear less, measure up in comparison.

Thanks for the continuing story.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on July 06, 2013, 03:53:08 am
Hi,

I have the Hartblei loupe, too. The reason I am not so happy with it has a lot to do with viewing position.

I am not happy looking down. Also I am a short person and I need to rise the camera as high as I can to get above obtrusions, like bush, guide-rails and so on.

So I went with the PM5 prism, but it has no adjustable ocular, try to get a lens made for it. The Zeiss 3X is essentially a telescope and magnifies the image additionally, so I could use it with my PM5 or with my Hartblei 4X. It is darned expensive, and I have not seen it. It has been recommended by Joseph Holmes and Lloyd Chambers. My understanding is that PM5 with the Zeiss is more like 9X. I will have it in one or two weeks and report back.

http://www.josephholmes.com/news-sharpmediumformat.html

Regarding the Hasselblad HC120 MacroII it seems to be in a different league than the Zeiss 120/4 according to MTF data. Let's say you check MTF 20 mm of axis at 40 lp/mm and at aperture f/8. 20 mm of axis is near corner on FF 135, but not even edge on a P45. Edge on P45+ is 24.5mm and corner is 30.6 mm.

InfinityMacro
Zeiss 120/4 Macro Planar30%55%
HC 120/4 MacroII65%65%

The Macro Planar has six elements while the HC 120/4 Macro has nine. The HC 120 macro has clearly some kind of internal focus/floating element design, that is normally needed to keep field curvature down over different focusing distances. Minimum focus distance (object to film) is 39 cm, this makes i clear that elements move while focusing. With non moving elements the minimum focusing distance at 1:1 would be 48 cm (it is always 4X the focal length).

http://www.hasselblad.com/media/2459990/hc120-ii%20v2.pdf

http://www.hasselbladhistorical.eu/pdf/lds/CFi120.pdf

Best regards
Erik




Erik, I have a Hartblei loupe (500c/m P20 back) and find it makes a huge difference to my focus ability. I was brought up on the reverse view so it is second nature but I can see why it would trouble others. I am curious as to why you would go from the 4x down to 3x? You will gain the comfort of 'correct" viewing but loose the extra magnification an interesting compromise the outcome is awaited with interest.

 I'm a Makro Planar fan as well and would be interested in how the highly praised H series 100mm and the 120 H Macro, of which I hear less, measure up in comparison.

Thanks for the continuing story.

Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Stefan.Steib on July 06, 2013, 06:44:28 pm
Hi Eric

Comparing a fully mechanical to an electronical controlled camera is tricky nowadays.
You need to push up sharpening until it matches the Sony , even if you don´t do anything the firmware in the modern DSLRs is already sharpening images,
not only linear but also according to their specific lens data, these lenses are all chipped.

The DPReview data were measured also on the full available shift amount means 44x56mm format.

at f11 the field curvature at infinity will not be visible anymore.

BTW - the flare that you mentioned with the Zeiss standard Hasselblad lenses I can confirm, we did 2! additional lightraps for our Superrotators as well as a complete
capsuling for the TS mechanism to improve that, and - gues what, there is none left. May also have a connection to our nearly round 12 blade aperture, the effects of the 5 shutter blades
of the Blads lenses are definitely well known and sometimes upright ugly especially in defocused areas.

The Hartblei loupe works best on the HCam, you look into the sliders direction straight to the motive. Works pretty good.

Greetings from Germany
Stefan

Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on July 07, 2013, 12:34:52 am
Hi Stefan,

Sorry, I missed the shifted test on DPReview. I think you are wrong that firmware would sharpen raw images. But I know that things happen that you normally don't see, some lens correction data is applied automatically, say in Lightroom. I have seen that on my Sony RX-100. Lens distortion is removed automagically in LR. Raw developer (Iridient) didn't do that.

I mostly compare the Macro Planar to my Sonnar 150/4. That lens is sharp corner to corner at f/4.

It is of course possible that my sample of the Planar Macro is a bad one.

Could you please explain the Zeiss and Hasselbald MTF curves? I don't think Hasselblad would publish MTF data for a bad sample. All MTF tests I have seen were similar, Zeiss, Photodo, Hasselblad. Both Zeiss and Hasselblad curves show a very high drop of for MTF at infinity. At close range the MTF curves are much better, similar to the Sonnar 150 at infinity.

Thanks for mentioning the changes Hartblei made to the 120/4 macro lens group. The circular aperture is nice for sure. The internal reflections I have seen in my early tests were coming from the Arax adapter, but now I shooting on a Blad.

Initially I used the Hartblei focusing hood. I agree that it is nearly optimal. But I switched to the PM5, because I am not comfortable with the viewing position. Trying to improve my focusing technique.

It would be helpful if you posted a good image using the 120/4 at f/11 on full frame MFD. The image would preferably have fine detail in the corners (treetops are fine).

I have the following lenses:

50/4 Distagon CF/FLE
80/2.8 Planar CFE
120/4  Planar Macro CF
150/4 Sonnar CF

I still work on focusing technique.

Best regards
Erik

Hi Eric

Comparing a fully mechanical to an electronical controlled camera is tricky nowadays.
You need to push up sharpening until it matches the Sony , even if you don´t do anything the firmware in the modern DSLRs is already sharpening images,
not only linear but also according to their specific lens data, these lenses are all chipped.

The DPReview data were measured also on the full available shift amount means 44x56mm format.

at f11 the field curvature at infinity will not be visible anymore.

BTW - the flare that you mentioned with the Zeiss standard Hasselblad lenses I can confirm, we did 2! additional lightraps for our Superrotators as well as a complete
capsuling for the TS mechanism to improve that, and - gues what, there is none left. May also have a connection to our nearly round 12 blade aperture, the effects of the 5 shutter blades
of the Blads lenses are definitely well known and sometimes upright ugly especially in defocused areas.

The Hartblei loupe works best on the HCam, you look into the sliders direction straight to the motive. Works pretty good.

Greetings from Germany
Stefan


Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on July 13, 2013, 03:34:22 am
Hi Stefan,

I have shot a new aperture series at my favorit castle (just being 10 km from my office makes it favorit) with Sonnar 150/4 and Macro Planar 120/4 and it confirms your observations. These images were shot on Hasselblad 555 ELD with a P45+ back. No electronics involved.

The aperture series is here: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/Lenses/SonnarVSPlanar.html

I am aware of the modifications Hartblei did on the TS lenses.

Best regards
Erik


Hi Eric

Comparing a fully mechanical to an electronical controlled camera is tricky nowadays.
You need to push up sharpening until it matches the Sony , even if you don´t do anything the firmware in the modern DSLRs is already sharpening images,
not only linear but also according to their specific lens data, these lenses are all chipped.

The DPReview data were measured also on the full available shift amount means 44x56mm format.

at f11 the field curvature at infinity will not be visible anymore.

BTW - the flare that you mentioned with the Zeiss standard Hasselblad lenses I can confirm, we did 2! additional lightraps for our Superrotators as well as a complete
capsuling for the TS mechanism to improve that, and - gues what, there is none left. May also have a connection to our nearly round 12 blade aperture, the effects of the 5 shutter blades
of the Blads lenses are definitely well known and sometimes upright ugly especially in defocused areas.

The Hartblei loupe works best on the HCam, you look into the sliders direction straight to the motive. Works pretty good.

Greetings from Germany
Stefan


Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: EricWHiss on July 14, 2013, 04:08:29 am
Bart,
Transmissive step wedges (as opposed to printed step wedges) cover more range (over 13 stops)  so are therefore more useful for DR testing of current digital cameras. I'm 'sorry' that you have been confused.  They are available from Stouffer for about $35 but perhaps other sources as well.   
Eric



Hi Eric,

Sorry, but shooting a step-wedge is not more accurate, although may be closer to variable conditions real live shooting situations (partly due to veiling glare), depending on the lens and lighting situation used. For a fair, unbiased review one usually tries to avoid as many variables (such as lens / lighting conditions used) as possible. Ignoring things like these variables is exactly what makes comparisons controversial.

The DxO Mark evaluations seem to be pretty accurate though.

Cheers,
Bart
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on July 14, 2013, 05:32:34 am
Hi,

I have a Stouffer wedge 41 steps, but I didn't get around to shooting it. You need to eliminate all surrounding light and flare. It is not easy.

Best regards
Erik
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: Bart_van_der_Wolf on July 14, 2013, 07:04:12 am
I have a Stouffer wedge 41 steps, but I didn't get around to shooting it. You need to eliminate all surrounding light and flare. It is not easy.

That's correct, I know from personal experience (I have various Stouffer step wedges, reflection and transmission versions) that the biggest variable can come from the shooting conditions (just like in real life, but unwanted for an objective test).

Veiling glare is the proverbial elephant in the room, and surface reflections can also spoil the quality of the test.

Cheers,
Bart
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: EricWHiss on July 14, 2013, 02:09:12 pm
Hi,

I have a Stouffer wedge 41 steps, but I didn't get around to shooting it. You need to eliminate all surrounding light and flare. It is not easy.

Best regards
Erik

Just cut a small window out of a black matte board or something similar and tape the transparency wedge to the back from the edges.  Use a large enough matte board to cover your light source.  
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on July 14, 2013, 02:50:56 pm
Update: samples reshot

A series of samples were shot and checked with RawDigger, the most ETTR exposures without clipping were chosen.



Perhaps some of this is useful: http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/RawImages/Stouffer/

Best regards
Erik
Title: P45+ on a Hasselblad 555ELD, Stouffer wedge some comments
Post by: ErikKaffehr on July 15, 2013, 02:36:13 pm
Hi,

Some comments about the Stouffer wedge shots.

1) Tried to shield external light as much as possible.
2) I guess flare limits DR on both Hasselblad and Sony. Macro lenses used on both. Planar 120/4 and Minolta 100/2.8 AF

Here are the evaluations by Imatest:

(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/RawImages/Stouffer/Results/20130714-CF043507_Step_2.png)(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/RawImages/Stouffer/Results/20130714-_DSC2289_Step_2.png)

So the Sony Alpha 99 has about one EV advantage. This is much less than DxO measurement on both cameras but DxO may use a better test target? http://www.dxomark.com/index.php/About/In-depth-measurements/DxOMark-testing-protocols/Noise-dynamic-range
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: EricWHiss on July 16, 2013, 12:50:50 pm
Your imatest numbers are definitely less than mine for testing similar backs (p20, CF 22, CF 528, CF 39, etc) however I can't say why yours are lower and I haven't run your files through imatest myself.  In my own testing, the imatest low values come closer to DXO's values and also fit with the sensor manufacturers stated DR.    But does DXO test camera and lenses or just the sensor?  Lenses may limit contrast and therefore DR - so they may have some effect.  In fact as a side discussion, I wonder what the DR limits of lenses are?  I've read somewhere that the most we can expect through good real life lenses is about 13-14 stops. Anyone have any info on that?  Certainly we are at the point where the lenses can make the difference.

Since I have tested many cameras, the thing I find most useful is the ratio of drop from low to high values in imatest.  DSLR's of past used to drop quite a lot from low to high - ie about 4-5 stops.  Current generation DSLR's like the Nikon d800 don't drop as much between the ratios.  I find the Imatest High value of most use to evaluate how an image will hold up through the editing process.
Title: Re: My journey into MF digital, starting with a P45+ on a Hasselblad 555ELD
Post by: ErikKaffehr on July 16, 2013, 03:28:00 pm
Hi Eric,

In this conversion I have used Imatest internal conversion, based on DCRaw. I can get much better results using LR4, for instance.

The first test I have done was with the 24-70/2.8 ZA lens but the second one was made with the Macro 100/2.8. The Macro 100/2.8 gave much better results which may depend on less internal flare.

The DR you can get trough a lens depends much the size of the brightest patch. According Norman Koren's test most good lenses have about 0.5% flare (or so), that would limit DR to about 8 stops. If the bright patch is small it would be possible to have a much higher DR.

In practice I can see a DR of about 9-10 EV in my raw data, using RawDigger. I have found some files with wider DR but those typically included the sun (like setting sun).

Of the about 65000 images I have on my computer I guess that a few dozens are limited by DR. I have just found a couple of images that really got better by multiple exposure HDR, but in many cases some significant tone mapping effort has been necessary to make a good image.

http://echophoto.dnsalias.net/ekr/index.php/photoarticles/61-hdr-tone-mapping-on-ordinary-image

Best regards
Erik



Your imatest numbers are definitely less than mine for testing similar backs (p20, CF 22, CF 528, CF 39, etc) however I can't say why yours are lower and I haven't run your files through imatest myself.  In my own testing, the imatest low values come closer to DXO's values and also fit with the sensor manufacturers stated DR.    But does DXO test camera and lenses or just the sensor?  Lenses may limit contrast and therefore DR - so they may have some effect.  In fact as a side discussion, I wonder what the DR limits of lenses are?  I've read somewhere that the most we can expect through good real life lenses is about 13-14 stops. Anyone have any info on that?  Certainly we are at the point where the lenses can make the difference.

Since I have tested many cameras, the thing I find most useful is the ratio of drop from low to high values in imatest.  DSLR's of past used to drop quite a lot from low to high - ie about 4-5 stops.  Current generation DSLR's like the Nikon d800 don't drop as much between the ratios.  I find the Imatest High value of most use to evaluate how an image will hold up through the editing process.
Title: Dynamic Range C1 convertion
Post by: ErikKaffehr on July 16, 2013, 09:12:09 pm
Hi,

This was converted by C1 (linear conversion, default settings).

Note higher SNR in medium and high tonal range. This reflects higher photon count, probably, it is expected. Liking C1 a bit better, learning all the time ;-)

Note: in my samples, the right and of the wedge is blackend out by a credit card on top of the wedge. There is a small light leak giving a false step in some developments. This was cropped out in the latest conversion. Might be a small disadvantage for Sony, as some data were cropped away.


Best regards
Erik




(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/DynamicRange/Results/20130714-_DSC2288_C1_1_Step_2.png)(http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/DynamicRange/Results/20130714-CF043506_C1_Step_2.png)