Luminous Landscape Forum
Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: EricWHiss on May 19, 2011, 01:41:11 am
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I had all the cameras sitting here and wanted to make a quick test to see how they performed for my own curiosity and decided to share the results here. I am only presenting images of the step wedges and do not have any quantitative data to share because I don't have a Mac version of Imatest yet (Hey Norman - how about that beta?) and wasn't at the studio to use the light table so this was just a quick test using my NEC monitor to light the step wedge - definitely not perfect. The idea was to shoot the stoufer transmission step wedge and see how much the shadows could be brought up. I exposed to get the #1 wedge as close to clipping as possible when the file was set to linear with no other adjustments. I then imported all the files to Lightroom and reset curves in each file to linear, blacks and both color and luminance noise reduction all to zero. I am sure that were I to use C1 for the phase files or phocus for the CF files I might get better results so this is just for a quick comparison. Each step in the stouffer transmission chart is about 1/3 a stop, but more importantly how does each file hold up and how much can the files be lifted?
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I was a bit surprised how close they all looked - except for the P20 file - it looked correctly exposed in C1 but is showing down a stop in LR3 for some reason. Anyhow, examine next the same files pushed up 3 stops in exposure in LR3. This is where you can see the real differences. I could have pushed the CFii-39 and AFi-ii 12 up to 4 stops but the canon file already looked terrible.
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Just for fun, I added a set with the CF-ii 39 back set to multishot mode. btw - The spots outside the step chart are really marks in the black matte board.
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Notes:
The CFii-39 in multishot mode seems to be the best overall.
The Leaf file is really large but the noise profile is pretty good zoomed in and is probably the best single shot. At 4 stops exposure adjustment the two halves of the sensor are visible.
The Leaf file is hard to white balance because it's changing from light to dark. Balance the brightest side and get a red shadow tone, or balance shadows and get a green tone (regardless of input color profile).
The Canon 5D2 has obvious pattern noise and not usable pushed 3 stops
The lens used for all the digital backs was the Rollei 90mm apo macro.
I do not plan to make the RAWs available, but may provide 100% crops at a later time - but not sure they are needed.
I would like to see the IQ 180 at the lower ISO 32 setting and also with sensor plus activated at base ISO.
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I really love my Hassie 39Mp. There is always a lot of people saying Phase and Leaf are better than Hasselblad, but as you Eric, i always try myself and came to the conclusion that Hasselblad is no way worse than Phase or Leaf. That is why so many professionals are using Hasselblad. Same with the lenses. I have had the three schneider LS on a DF...... no better than the Hasselblad HC lenses. ::)
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Yes, I agree with you Peter. ;)
Actually, I think the best back I've used is still the ixpress 528c (at least at base ISO). I really liked the color and DR. Now that I've had both the 528c and the AFi-ii 12, I can be sure the 528c did outperform the Aptus 12 in microstep mode. I'm sort of experimenting with lenses a bit now - haven't tried any of the H lenses yet but did test the Phase (and Schneider) 80mm LC and thought it was okay - but just that.
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I really love my 528c also but i will be selling it. I just have to make some pictures of it. I also use my 384 very often because i really love the square format. I hope to get a 5000 euro for my 528c with hasselbladH or HasselbladV adapter. The microstepmode is not surpassed by any back i have ever seen.
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A lot of the information in the files from the Canon 5d2 is in the highlights whereas my digital back doesn´t respond to highlight recovery half as good. There is not much to gain by pushing a file from the 5d2 by 2 stops or more.
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A lot of the information in the files from the Canon 5d2 is in the highlights whereas my digital back doesn´t respond to highlight recovery half as good. There is not much to gain by pushing a file from the 5d2 by 2 stops or more.
The exposure in the test is set such that the top wedge is the highest possible without clipping *in linear mode* therefore there is nothing to recover. The exercise shows the total range possible - either its there or it isn't. If I set the exposure higher, the first few steps look the same and don't recover. But of course you are absolutely free to set up your own tests if you think there is something more here to discover.
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Thank you for doing this test. How do you suggest I should interpret the (+3 stops) image files? Is the thing to look for when one no longer can discern discrete steps towards black? Or when the noise level become unbearable?
It would have been interesting to see how the Nikon D7000 would do in this test.
Can a monitor be "trusted" in terms of flickering etc for this kind of measurement?
Since this test is artificial, how relevant do you think it is for more realistic scenes (where, if any, in-camera noise reduction would have a harder time)?
Perhaps an improvement to this test would have been analyzing the linearity from black to white (spatial averaging), and the noise level. A perfect camera (in this sense at least) then would have an even staircase response from 1 to 41, and no noise (variance) within.
-h
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That's a good question and you're welcome. In looking at the files, I just try to imagine my own images with the shadows lifted that much and what noise I would see in the images. Originally I intended to post images with the shadows lifted or fill light setting set to max, but this method differs so much from one application to the next that I used exposure instead. I also took some real life comparison shots which I may post soon. This will help show the same thing.
ps. I forgot to add exposure times were over a second so flicker was not a concern.
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Eric -
Seems like there are three parts to this:
1) the making of disciplined real-world apples to apples comparisons from one back to another
2) the technique used to make the test - is it good enough? Is the lighting a factor?
3) reading the test - what do we look for?
To read the test, it seemed we should look at the "edge lines" from step to step, and when they were lost. I'm not quite understanding the lighting technique behind the test yet.
But boy, its great to see actual hands-on "torture tests" from back to back. We rarely see that, and thanks for doing this!
Geoff
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Hi Geoff,
Yes that's more or less it - look to see where the dark steps become distinct but also look at the noise level and see if that is usable or not. In a real image, one might have a reason to lift shadows or adjust exposure and this is just an easy way to compare as the lighting was constant and the wedge gives us a usable measure of the DR. eg. 30 steps is 10 stops.
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I am sure that were I to use C1 for the phase files or phocus for the CF files I might get better results so this is just for a quick comparison.
Eric, what a fun test (at least for us nerds).
Two thoughts:
- I would have loved to see a textured material or other detailed subject matter alongside the smooth stepper chart. Obviously harder to find a stepper pattern with texture/detail, especially the 3 dimensional (rather than printed) kind.
- I would love to compare the Canon, Phase, and Leaf files in Capture One vs. LightRoom vs. Etc (my interest dwains quickly after that, but Aperture, Irrident Raw Developer would be my next two). In particular the pattern noise in the Canon, in my experience, is much better handled in Capture One.
Part of the real world application of dynamic range, in my opinion, is not only how much noise you get, but what KIND of noise and how well it can be handled by the raw processor of your choice, and how that noise+raw_processor affects the overall look of the image, tonal transitions, and detail. That's why I say I'd love to see both textured/detailed material as well as including software in the mix, especially when Hassy and Team Phase One (Leaf/Phase) but a lot of effort into eaking out that last bit of detail/information in the file, often through proprietary/dedicated means (e.g. the black cal file).
I'd much rather have those two things than "quantitative" Imatest data which is quite one dimensional in it's real world application.
Still, I want to emphasize my appreciation for your test and your efforts. I know all too well that no matter what test you run or how carefully/well-meaning someone (actually many people) will find something they would have done differently.
Doug Peterson (e-mail Me) (doug@captureintegration.com)
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No wonder many of the finest museums use the CF39 MS. Put an APO Digitar in front of the back and the results are nothing short of breathtaking.
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Doug,
Thanks and as you can imagine I did look at the files in C1 because that is what I mostly use for everything except the hasselblad files which aren't supported. I looked at NR and shadow lifting for each file in several applications and there are big differences of course and though I'd like to show all of that it's just too much work. I think C1 does a great job with the 5d files overall but LR3 does seem to really have great NR. That's certainly important to figure into these tests because in a real image you would use some NR and I've presented here only images with NR off.
I'll post some real images and crops of the shadow areas sometime in the next days.
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Here are some examples of how this shadow lifting would look with real images. I took the same scene from my window yesterday with the 4 different backs. I tried to expose the images as close to but not blowing out the white plastic bag in the center of the frame.
First the Hasselblad CF-ii 39MS back with 60mm Schneider Curtagon lens:
First shown whole frame images with no adjustments, and shadows lifted to 100%
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Here are some zoomed crops of the darker areas after being lifted with the shadows tool, note that I did not change any NR or other settings - only the shadows.
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Here is the same set of images in the same format for the Canon 5D2. Shot with the 24-105L lens, and only adjustments were to raise the shadows slider to 100. No NR. Note that its still pretty dark. I think this is where you can see that MFDB's have more DR. A portion of the white plastic bag is blown out in this image already so I could not expose more or I would lose information on the top. All of the digital backs have more room in the shadows without blowing out the bag.
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And lastly from the Leaf AFi-ii 12
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By the way the Leaf crops were presented to be about the same portion of the frame - here's a 100% crop with no noise reduction. I should also mention, I was doing two tests at once here because I wanted to test for purple fringing and for infinity focus. The lens was only stopped down to f/5.6 and focused at full infinity stop so this region is not as sharp as it would be were I to have either stopped down or focused closer in from infinity. I only mention this as you will be looking at a 100% crop and don't want people to believe the back can't get detail - that it can do and in spades.
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Conclusions:
After manipulating the files in various programs and experimenting to see which methods and programs (ie. shadows, fill light, exposure adjusts, curves, NR, etc), I've found where I personally would consider the maximum usable DR for each camera/back. I simply tried to find the best shadow lift combination where the noise reduction could still control the noise level enough to make a satisfactory print. I looked at the wedge and recorded the darkest discernible level and converted to stops. Probably Imatest would do much much better at quantifying these data, and even then I suspect that many of you out there are working with different definitions of DR, so for the sake of argument (or rather to avoid arguing) I'll call these numbers Eric's usable DR figures or EDR. I find looking at what will be usable in print a much more useful number than a manufacturers spec or a number from DXO but YMMV. Note that this does not really take in account for the differences in pixel count. Also worth noting the first aptus 12 I had for testing seemed to perform a bit better.
Canon 26 steps = 8.7 stops EDR
Hasselblad CFii-39 in single shot 33 steps = 11 stops EDR
Hasselblad CFii-39 in multi-shot 35 steps = 11.7 stops EDR
Leaf Aptus 12 32 steps = 10.7 stops EDR
Phase p20 (non plus) 29 steps = 9.7 stops EDR
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Thank you for your time, effort and articulate presentation. Seems like quite useful stuff. I would have liked to see a newer generation Hasselblad sensor (one of the Kodak Truesense something I believe it's called, from the h4d40, h4d50, and/or h4d50 MS ) thrown in the mix, but hey ... you can't have everything in life :) . Also a P65+ , IQ160, H4d60 thrown in the mix (the other Dalsa sensor before the 80) would have been interesting, and hell why not an iq180 at iso 32 :))) ... I know, I'm being shameless here ... :)
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Hi Eric!
Seems like the Leaf 12 is coming out poorly in your test.
What do you think about this back asides from the dr?
Henrik
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Hi Eric!
Seems like the Leaf 12 is coming out poorly in your test.
What do you think about this back asides from the dr?
Henrik
Hi Henrik,
Well I would not say it was doing poorly exactly ESP. considering it has twice the pixels. What did you think from the sample images?
I must say that this is my third aptus 12 back. The first one was a loaner for testing generously provided by Paul Slotboom of Optechs Digital and it was nothing short of brilliant. That one pulled a 34 step and would have been the best overall single shot plus it had none of the purple fringes that I'm seeing on occasion with the other two. Based on the loaner's performance, I purchased one which had unluckily had some problems and needed to be sent back. The replacement does not appear to be as good as the loaner. The promise is there though. I like a lot about it and would be 100% satisfied with an equal to the loaner as I like the features of the back overall.
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That is strange. Do you know which one is the newer?
I have heard that there have been two different productions of the sensor because
Leaf ran dry. Could there be a quality-differense between the two batches?
Henrik
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Henrik,
Thats interesting - I wonder if there is a way to tell from the file EXIF data? I can see the loaner had V 5.2 firmware while the others have V 5.1 but Yair didn't think that would make a difference. I can see a difference in the black file when really pushed - the sensor is made from 4 smaller rectangles and did note a difference - one chip the the diagonally opposed squares were matched and on the other the halves were matched (like the CFii-39MS) but didn't think this was important.
Eric
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Thank you for your time, effort and articulate presentation. Seems like quite useful stuff. I would have liked to see a newer generation Hasselblad sensor (one of the Kodak Truesense something I believe it's called, from the h4d40, h4d50, and/or h4d50 MS ) thrown in the mix, but hey ... you can't have everything in life :) . Also a P65+ , IQ160, H4d60 thrown in the mix (the other Dalsa sensor before the 80) would have been interesting, and hell why not an iq180 at iso 32 :))) ... I know, I'm being shameless here ... :)
Yes, I'd really like to have seen the IQ 180 and the newer hasselblad backs but neither are made to fit on my cameras. My understanding from Doug Peterson is that the IQ 180 mostly will differ in long exposure times and sensor+ but we'll probably see once users have had them for a while.
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I'm not trying to make excuses for Phase/Leaf but the 80MP chip is still very new and I imagine the firmware in the back is still not as optimised as the other much more established Hasselblad backs used. The P65+ got quite a few FW upgrades after launch to improve IQ so I suspect the IQ180 will get the same.
Excellent test and brilliant nerdy reading! ;)
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Eric
If you can get your hands on a pentax k5 it would be interesting to see the results
I'm continually blown away with the DR of this little camera. It's going to be interesting which has wider DR the k5 or the IQ180?
Marc
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Hi Eric.
Excellent test. Thanks for sharing.
How about image quality feeling? No mechanical, only feeling...
As you know, I'm using cf-39ms but I like leaf back tonality.
I'm very interested in new aptus12.
Cheers.
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Hi Eric.
Excellent test. Thanks for sharing.
How about image quality feeling? No mechanical, only feeling...
As you know, I'm using cf-39ms but I like leaf back tonality.
I'm very interested in new aptus12.
Cheers.
Thanks Guys,
Chiek, good point to bring up - the tonality or feel is very important aspect, and I did do some testing vs the other cameras. I'll be happy to post that stuff, but probably best to start another thread which I'll do in a couple days. I also looked at how each camera could render detail through the aperture range and really quite a lot of other stuff.
Mark - yes would love to get my hands on the K5 as I've heard good things
Gawas - probably you are right and I hope so too! I got sample files from Leaf that had higher rev versions of firmware, and the loaner back also had a higher rev so we at least know they are working on it.
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Here is a K5 example, I've never been able to point a camera straight up and capture both highlight and shadow detail until now!
Marc
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Marc,
Looks impressive, thanks for sharing. I checked DP Review who also shoot a stouffer wedge and they are reporting 29 stops which would put it between Canon 5D and the digital backs but their testing method may differ from mine. http://www.dpreview.com/reviews/pentaxk5/page14.asp
Eric
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Unfortunately they test an in camera jpeg not a RAW. The K5 trumps my P45+ with regards to DR but I don't have them side by side for a good RAW comparison
I'm hoping the IQ180 is at least close (within a 1/2 stop) of the K5 I think DxO mark tests are valid so time will tell
Marc
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Marc,
Sounds really impressive. Would it be possible for you to post a side by side of the K5 vs. P45+?
Thanks,
Eric
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Marc,
Sounds really impressive. Would it be possible for you to post a side by side of the K5 vs. P45+?
Thanks,
Eric
sent the P45+ in for trade on a IQ180 so I no longer have it, I have my fingers crossed that the IQ180 will come close to the K5 with respect to DR
Marc
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sent the P45+ in for trade on a IQ180 so I no longer have it, I have my fingers crossed that the IQ180 will come close to the K5 with respect to DR
Marc
How come you are allowed to say about the K5 what I have been saying about the D3x for 2.5 years, and nobody calls you a DSLR troll? ;D
Cheers,
Bernard
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How come you are allowed to say about the K5 what I have been saying about the D3x for 2.5 years, and nobody calls you a DSLR troll? ;D
Because no MF shooter feels threatened by a Pentax K5. Whereas they do feel threatened by a top-end Nikon.
John
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Because no MF shooter feels threatened by a Pentax K5. Whereas they do feel threatened by a top-end Nikon.
John
I don't understand why anyone would feel threatened unless they have a financial arrangement with a specific brand, but what anyone uses really is up to them.
I know 4 very good photographers that went from their backs to the d3x and never blinked and I thought about it since I have a full case of Nikon glass. The only thing that stopped me was I like the 1ds3 skin tones and with the Nikon I was told you can't see the lcd when tethering.
But cameras, it's all up to the person. I'd rather use my p21+ than my p30+ because it's so much faster and responsive. My best friend just returned from shooting the stars at Cannes and he only uses a p21+ on a V system and he is one of the few photographers I know that for commerce, with his contract, every print goes to 60 inches minimum.
It's all about what you are comfortable with.
IMO
BC
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How come you are allowed to say about the K5 what I have been saying about the D3x for 2.5 years, and nobody calls you a DSLR troll? ;D
Cheers,
Bernard
Actually that's another camera I wish I had to test with. For my DSLR - I went Canon early on and started using my Leica and olympus lenses on it plus a few Canon so there became too much inertia to move over. And the underwater housings get expensive for the D3X and 1DS bodies compared to the 5D2 so I just stayed with the canon, but my belief is that the D3X is better than the 5D2 for sure. But the 5D2 is quite behind in many ways to the MFDB that I tested.
Bernard did you compare the D3X to the Pentax 645D?
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Also ISO 160 is lower noise than iso 100 on the 5DII
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Also ISO 160 is lower noise than iso 100 on the 5DII
last time i said that on this forum i was told different and given a technical explanation as to why it isn't ???
i still use 160/320/640 as to my eyes the images are less noisy and pattern noise in the blacks is greatly reduced.
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Hi,
Miles Hecker did a comparison shoot of the P645 and the D3X. It was here on these forums, I cannot find it right away.
Best regards
Erik
Actually that's another camera I wish I had to test with. For my DSLR - I went Canon early on and started using my Leica and olympus lenses on it plus a few Canon so there became too much inertia to move over. And the underwater housings get expensive for the D3X and 1DS bodies compared to the 5D2 so I just stayed with the canon, but my belief is that the D3X is better than the 5D2 for sure. But the 5D2 is quite behind in many ways to the MFDB that I tested.
Bernard did you compare the D3X to the Pentax 645D?
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It's all about what you are comfortable with.
IMO
BC
Here in France ze french zey say: "Chacun à son gôut."
I guess DR and ISO is the last frontier for still phtography, now that megapixels have multiplied obscenely.
Edmund
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Here in France ze french zey say: "Chacun à son gôut."
I guess DR and ISO is the last frontier for still phtography, now that megapixels have multiplied obscenely.
Edmund
Edmund,
There is more for the last frontier of digital; improved (pleasing) color palettes and finer color gradations, and highlight transitions... Those seems to me as no less interesting and as very hopeful with the Aptus/Afi-II 12 and IQ180 backs... possibly making them more on terms in those regards with... something called, ehhh... slide film.
Regarding comparing MFDB to DSLR for DR and more, is it not that the DSLRs are tuned different and with in camera algorithms to with noise reduction and more achieve high ISO and DR? While if we look at optimum image quality they do not win...
Horses for coarses, or what is the saying?
Regards
Anders
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I exposed to get the #1 wedge as close to clipping as possible when the file was set to linear with no other adjustments. I then imported all the files to Lightroom and reset curves in each file to linear, blacks and both color and luminance noise reduction all to zero. I am sure that were I to use C1 for the phase files or phocus for the CF files I might get better results so this is just for a quick comparison. Each step in the stouffer transmission chart is about 1/3 a stop, but more importantly how does each file hold up and how much can the files be lifted?
Eric,
Your results are quite informative, but how do you know that your files are fully exposed too the right. Lightroom and ACR use a BaselineExposure (see page 32 of the linked PDF (http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/products/photoshop/pdfs/dng_spec.pdf)). For my Nikon D3, the offset is +0.5EV. I have found that setting exposure to -0.5EV in ACR to compensate for the +0.5 EV offset and using a linear tone curve as you have done gives a reasonable approximation to the actual raw values when using a Stouffer wedge. Without the exposure adjustment, a proper ETTR exposure appears clipped. For many dSLRs one can use a program such as Rawnalize, DCRaw, or Iris to examine the raw data directly without white balance or a tone curve. I do not know is such a program is available for MFDBs.
Here is a D3 with a stouffer wedge fully exposed to the right as shown by Rawnalize and the ACR preview of the same file with default settings.
(http://bjanes.smugmug.com/Photography/Exposure/ACR-Exposure-Offsest/005RawHistogram/306816807_tVzJt-O.png)
(http://bjanes.smugmug.com/Photography/Exposure/ACR-Exposure-Offsest/005ACRdef/306816817_j8Fk9-O.png)
Some Phase One cameras such as the P65+ overexpose by a full f/stop to preserve highlight headroom as shown on the DXO ISO plots. I would imagine that the BaselineExposure would be +1 EV
(http://bjanes.smugmug.com/Photography/Exposure/ACR-Exposure-Offsest/i-hrTTqcQ/0/O/ISOP65PD3x.jpg)
Regards,
Bill
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Hi Bill,
Yes, good point to bring up. I shot tethered to C1 for the Leaf AFi-ii 12, Canon 5D2, and Phase p20 and tethered to Phocus for the CFii-39MS. I did notice the exposure differences in LR3 for the phase p20 but not the others.
Thank you for the information on the Nikon.
Off topic a bit but do you know why ACR/Lightroom use exposure offsets? And I'm not familiar with Rawnalize software so can you explain why in the chart you included the green histogram is ahead of the red and blue - what is that showing? Differences in sensitivity or ???
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Hi Bill,
Yes, good point to bring up. I shot tethered to C1 for the Leaf AFi-ii 12, Canon 5D2, and Phase p20 and tethered to Phocus for the CFii-39MS. I did notice the exposure differences in LR3 for the phase p20 but not the others.
Thank you for the information on the Nikon.
Off topic a bit but do you know why ACR/Lightroom use exposure offsets? And I'm not familiar with Rawnalize software so can you explain why in the chart you included the green histogram is ahead of the red and blue - what is that showing? Differences in sensitivity or ???
Eric,
Rawnalize was a freeware program published by GaborSch, who unfortunately has passed away as detailed on this link (http://forums.dpreview.com/forums/read.asp?forum=1018&message=36104145) on DPReview. The green channel of to the right of red and blue, because the program shows the raw channels before white balance.
Here is the Adobe explanation for the use of exposure offsets. Personally, I do not think that they are a good ideal. You can determine the baseline offset by converting the raw file to DNG and then reading the BaselineExposure with an EXIF editor.
Regards,
Bill
(http://bjanes.smugmug.com/Photography/ACRBaselineOffset/i-PJXDn25/0/O/AdobeBaselineExposure.gif)
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PRICELESS!!!
Because no MF shooter feels threatened by a Pentax K5. Whereas they do feel threatened by a top-end Nikon.
John
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Adobe says: (http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/products/photoshop/pdfs/dng_spec.pdf)
Some [camera models] leave a significant amount of highlight headroom during a normal exposure. This
allows significant negative exposure compensation to be applied during raw conversion
Negative? Wouldn't highlight headroom allow for significant amounts of positive exposure compensation before clipping highlights? Or am I missing something obvious?
Thanks.
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Adobe says: (http://wwwimages.adobe.com/www.adobe.com/content/dam/Adobe/en/products/photoshop/pdfs/dng_spec.pdf)
Negative? Wouldn't highlight headroom allow for significant amounts of positive exposure compensation before clipping highlights? Or am I missing something obvious?
Thanks.
It is a bit confusing, but if a camera allows 0.5 EV of headroom, it underexposes by 0.5 EV. To have a centered histogram and a normal brightness for the image preview, the camera or raw converter has to increase exposure by 0.5 EV. ACR then uses an BaselineExposure of +0.5 EV. If the image were fully exposed to the right, the highlights would appear clipped in the ACR preview and histogram. One can "recover" the highlights by using -0.5 EV with the ACR exposure slider.
Regards,
Bill
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It is a bit confusing, but if a camera allows 0.5 EV of headroom, it underexposes by 0.5 EV. To have a centered histogram and a normal brightness for the image preview, the camera or raw converter has to increase exposure by 0.5 EV. ACR then uses an BaselineExposure of +0.5 EV. If the image were fully exposed to the right, the highlights would appear clipped in the ACR preview and histogram. One can "recover" the highlights by using -0.5 EV with the ACR exposure slider.
I understand what you're saying, just not what Adobe is saying in their PDF.
Adobe says highlight headroom ("underexpose by 0.5 EV" as in your example) allows for "significant negative exposure compensation to be applied during raw conversion." In other words that underexposed images allow for further underexposure in raw processing. That doesn't make sense to me. It is ETTR that allows negative exposure compensation, not AE metered images that by definition leave .5 EV headroom (as in your example).
Again, from Adobe's PDF:
Some [camera models] leave a significant amount of highlight headroom during a normal exposure. This
allows significant negative exposure compensation to be applied during raw conversion
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am i really the only one who is slightly turned off by the color of the MF samples compared to the canon? the sky? the trees! even worse in the crops....
i am with cooter, canon skintones make clients happy....
have been tempted by the d3x as well because of the DR, but then i come across one of my DMF or leica M shoots and remember spotting and dirt and that is that.....
the new phase 180 is the first back in a long time that actually interests me....8x10 quality for fun and clean and fast (enough) 20mpix at high iso sounds right...but i have a feeling the next canon will take care of that urge....and it really has been nice to not have any gear envy AND not spend silly money for 3? years now (since the 5dii came out....)
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Paul,
That's an interesting observation and probably a personal one. I think Canon can get good skin tones mostly through their DPP software but having shot the images and seen the scene firsthand, I'd say the backs are more true than the canon. That said, true isn't always the most pleasing. I'd take any of the backs over the canon myself (but am glad to have both for when I need good AF or high ISO).
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am i really the only one who is slightly turned off by the color of the MF samples compared to the canon? the sky? the trees! even worse in the crops....
i am with cooter, canon skintones make clients happy....
have been tempted by the d3x as well because of the DR, but then i come across one of my DMF or leica M shoots and remember spotting and dirt and that is that.....
the new phase 180 is the first back in a long time that actually interests me....8x10 quality for fun and clean and fast (enough) 20mpix at high iso sounds right...but i have a feeling the next canon will take care of that urge....and it really has been nice to not have any gear envy AND not spend silly money for 3? years now (since the 5dii came out....)
+1
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am i really the only one who is slightly turned off by the color of the MF samples compared to the canon? the sky? the trees! even worse in the crops....
i am with cooter, canon skintones make clients happy....
have been tempted by the d3x as well because of the DR, but then i come across one of my DMF or leica M shoots and remember spotting and dirt and that is that.....
the new phase 180 is the first back in a long time that actually interests me....8x10 quality for fun and clean and fast (enough) 20mpix at high iso sounds right...but i have a feeling the next canon will take care of that urge....and it really has been nice to not have any gear envy AND not spend silly money for 3? years now (since the 5dii came out....)
Yes the look of a file is a personal opinion. Always has been, film or digital, motion or still.
Regardless, I've set up multiple tech stations half a dozen times. One running my Contax and Phase backs the second station the 1ds3. (Actually now the third station the RED).
Same light, same subject, best settings through the dedicated software, EOS utility for Canon, C-1 V3, V5, V6 for the P21+ and _30+.
Each time the client commented they liked the look of the Canon files.
Now I've never had a client demand I shoot any still camera and they all defer to my judgement, but regardless that's the response that has covered editorial, lifestyle advertising, fashion, beauty and retail from 6 different art directors of all age ranges and experience.
I usually just go with the camera or back I feel is best and I'll admit I have an affection for the Contax, my current backs to me are kind of like a slow film that will look better later, or in other words we're going to do a lot of work in post.
The Canons I just see as an acceptable tool, but a very easy tool to use. I can't really fall in love with the Canons like I do the Contax, but for a lot of work the Canon is just an easy fit, especially with today's schedule and using continuous lighting.
Now, I'll admit I don't have a clue what anyone means when they say "ultimate Image Quality". I've probably read that phrase on this forum 1,000 times and from a professional standpoint don't get it.
If I need more dynamic range, that's my job to add fill light, or craft the scene. If I need more resolution than 22 mpx, I guess I'll need to find new clients because nobody's asking. If I need pleasing color I think that is very subject, scene, light depended, though the Canon out of the camera seems the closest.
But to be clear I don't see any professional digital camera as a certain format. 645 is a larger frame than 35mm but really not like the film days of 6x9, 4x5 or 8x10. No, not anymore and I don't think clients do either. They see the 27" monitor as the format, because that's what their looking at.
My 5d's I use for B camera video, though did shoot one editorial job with them as stills. I do believe they produce a sharper file than the 1ds3. Actually for the costs they're pretty amazing.
Now I recently saw some very nice raw files from a hd4 40 mpx hasselblad and it got me interested in the look especially the skin tones. It is a camera I'll try soon, when our schedule permits.
IMO
BC
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Interesting to read the praise for Canon 5d2 skin tones, because for me that's coming out of left field. James and Paul, just curious - are you just talking about out of the box files? Or are you doing your own profiles with X-rite color passport or ??? I think for the phase backs the skin can sometimes be not right but they have the excellent skin tone tools - all you have to do is save it as a style...
No question the 5D2 is a great camera and huge value for the money. I certainly like mine and do use it often, but its never my first choice. One of my biggest objections to the canon has nothing to do with tech - I just don't like the 3::2 format much.
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am i really the only one who is slightly turned off by the color of the MF samples compared to the canon? the sky? the trees! even worse in the crops....
The files are not white balanced.
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Interesting to read the praise for Canon 5d2 skin tones, because for me that's coming out of left field. James and Paul, just curious - are you just talking about out of the box files? Or are you doing your own profiles with X-rite color passport or ??? I think for the phase backs the skin can sometimes be not right but they have the excellent skin tone tools - all you have to do is save it as a style...
No question the 5D2 is a great camera and huge value for the money. I certainly like mine and do use it often, but its never my first choice. One of my biggest objections to the canon has nothing to do with tech - I just don't like the 3::2 format much.
I usually use our 1ds3's instead of the 5d2 for still work. The 3's have a usb lock on the body that is a lifesaver.
The 5d2's we use as B cameras for motion.
As far as color, I set it in camera and/or in dpp.
As far as medium format color, it's good, but with my backs the color is too sensitive. I set it in C-1 but on set if I want to show more of an exact look, we set a hot folder in lightroom where there is more adjustments per channel, at least easier adjustments per channel.
Now remember this is for client on set review not final processing. For final processing we use different programs depending on subject, light etc. and for final processing, we usually use C-1 for Canon and Phase files knowing we will be doing a lot in photoshop.
I agree with the 3:2 crop, I don't like it much either though in todays world we shoot a lot more horizontal than we do vertical (for a lot of reasons) so 3"2 is less problematic than 4:3. If it was all verticals 4:3 is much easier, but it's not a vertical world anymore, at least for our work.
So we keep one body with the standard 3:2 screen, one Canon with the 4:3 screen. One is marked horizontal one camera vertical. Seems silly but works.
Still given my choice and having enough light without worrying about shooting motion, I'd rather use our Contax'.
But what I want and what I'm required to do are sometimes different. With 14 models per day and 25 people on set every hour is a lot of money and a lot of imagery is required in still and motion and no longer do you hear "can you just shoot a little _________" (you fill in the blank video, vertical, horizontal, tight, wide etc.).
In fact I've found in the last few years if you ask a question like is this horizontal or vertical, tight or wide, full page or double truck, web or print, or outdoor, motion or still the answer is . . . . yes.
IMO
BC
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first: obviously the mf backs have more resolution and dr then the 5d...there is no question...can i get the same color from them all...probably...
i really don't believe in such a thing as correct color....i see what i like and hopefully my clients do too....
there is a color, texture (or lack of) combination that works out really well with the canons....i know from experience that there is nothing worse then shooting a celebrity and the files you are showing (back of the camera, screen, ipad,...) don't look flattering...
i hate the 3:2 ratio....always have, always will.....i really hope that the next generation of DSLRs finally break from the 35mm mold...there is no reason to stick with it (other then lenses) but there are other formats that could work with existing lenses....
regardless, the next model is always better and i am pretty sure we will see something in the 30-40mpix range (i am hoping more for 30) with DR better then the d3x across manufacturers....and with canon hitting the under 3000 pricepoint that hard with the 5dII, it has to be around that...unless you prefer sigma of course.....
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Well the lens has an image circle so any aspect ratio could be accommodated?
Personally I like 3x2 for landscape orientation as it is closer to the angle of view that 2 eyes give you, more natural to me.
But... I prefer 4x5 for portrait orientation probably because of a lifetime viewing pictures in books, magazines and prints with this aspect ratio
Marc
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last time i said that on this forum i was told different and given a technical explanation as to why it isn't ???
i still use 160/320/640 as to my eyes the images are less noisy and pattern noise in the blacks is greatly reduced.
ISO 160 on the 5D2 is obtained by using the hardware ISO 200, digitizing the file, and then multiplying all the raw values by 0.8 (similarly for 320/640 etc; for 125/250/500 etc, the next lowest ISO is used and the result multiplied by 1.25). Therefore the results are indistinguishable from using ISO 200 and applying EC in the converter (since that again is accomplished by multiplying the raw values by the appropriate factor, just done in the conversion software rather than in the camera -- perhaps more accurately if the converter uses floating point rather than integer math which the camera uses). There is an illusion that 160 has less noise because the camera meters for ISO 160 even though it shoots at ISO 200 (ie it is secretly doing 1/3 stop ETTR).
The 5D2 is about the worst DSLR to use for this sort of comparison. The camera has horrible pattern noise which renders the deep shadows pretty much unusable, and substantially cuts down on the useful DR. The issue turns out to be compounded by the color filters, the transform to a standard color space such as sRGB/Adobe/Prophoto amplifies this noise. As people have said, cameras using the new Sony Exmor sensors (such as the K5, D3x and D7000) do much, much better in this regard.
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And I'm not familiar with Rawnalize software so can you explain why in the chart you included the green histogram is ahead of the red and blue - what is that showing? Differences in sensitivity or ???
Did not see this interesting question answered (sorry if I missed it). The color filters of the sensor is fixed, that is regardless of white balance settings (just a software setting) the color filters on the silicon remain the same. This means that when Red Green and Blue channels will saturate depends on the color of the incoming light. And then there's sensitivity, ideally the sensor would capture all incoming photons and RGB would be equally sensitive, but in practice they are not. Red is usually (always?) the least sensitive.
A trick that some perfectionists use is to put a coloured filter on the camera to even out the sensitivities and match it for the given lighting condition (that is usually reduce sensitivity of the green channel). That way you can in some circumstances gain ~1 stop of extra dynamic range (not 100% sure about the 1 stop, but I think it is around that). You need to correct the color cast in post-production of course.
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Eric,
I love 5D2 skin in C1 and in DPP. I shoot a Macbeth chart, balance off of that. Strong light gets a nice file. The only camera I like better, at least out of the box, is the M8.
The 5D2 is remarkable. I have lots of cameras, ds3, two 5D2s, two backs, RZs, Sinar 4x5 to 8x10, an Arca F line, too many Leica film cameras, an M8, and M9. I don't shoot stills much these days, but when I do, and it has to be digital, I toss two 5D2s, a 35, two 50's, two 85s and a 135 into a bag, and get on with it. No BS, I just get to making photographs and forget all the science, magicical thinking, consumer psychology and angst involved with cameras and just make photographs that inspire my client, and hopefully me as well. While the 5d2s thmselves don't produce rapture and trancendence, it just works, all of the time, whenever asked, and you can use it for B roll as well. Oh yeah, thy are $2200 bucks, slightly more than the Leica 28 ASPH. All the talk about pattern noise and false ISO, read noise, blah blah blah is fine, but look at the photos coming from Libya, Afghanistan, Yemen. Beautiful images, inspiring. Mainly shot with 5D2s.
Carry on, I'm done.
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I don't like the 5D2 as a camera, I mean by that the way it feels and balance in my hand is not "right" for me. I don't like it's plastic feeling either compared to the 1D (wich also fits much better and more naturally in hand for me).
But I have to say that TMARK is right IMO.
The incredible thing of this camera is that it just works. Skin tones are great also in the sense that they are good right-out-the-box wich means less hassle.
I can't think of a more 4x4 camera in the world.
I find though that the 1D gives a more neutral point wich makes it IMO a better tool for using it in heavy post-prod, but the image right-out-the-box from the 5d2 is IMO superior.
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Eric,
I love 5D2 skin in C1 and in DPP..........snip
Carry on, I'm done.
+1
I don't care about numbers, or get flipped out over shadow noise. I mean every image goes through post and it takes about 5 minutes in photoshop to selectively add noise reduction in different tonal areas. We do this in medium format and the smaller formats, always have.
I'm with T-mark, just throw it in a bag and use it. Good gosh, we carry thousands of pounds of equipment and can use anything we want, but the Canons work, you don't think about them, you don't beat yourself up trying to make them work.
This image (shot with a 5d2 and one kobald bron hmi) and 18 other images are going into an advertising show next week of 11x17 and larger prints.
(http://ishotit.com/PARIS_HALLWAY2.jpg)
I doubt seriously if anyone viewing these images which are of mixed formats, really care or notice if it's got 1/2 more stop of dr, or 10% more or less noise and the people viewing are buyers of photography which is my core market.
IMO
BC
P.S. The single light fixture on this shot cost $9,000, the camera $2,000.
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I doubt seriously if anyone viewing these images which are of mixed formats, really care or notice if it's got 1/2 more stop of dr, or 10% more or less noise and the people viewing are buyers of photography which is my core market.
Dynamic range is more important in say landscape photography in natural high dynamic range light, so you in post-processing often need to compress the range to fit nicely in a print. In a studio condition with planned lighting there is wrong with your lighting or exposure if you need to raise shadows in post-processing.
When you don't need to raise the shadows 5Dmk2 works nicely. However, when you do need that, the line noise found in 5Dmk2 can be a very real problem. This is however not a generic DSLR problem, but a Canon problem which I truly hope they fix in their next model. Nikon D3x is currently the DSLR to compare with concerning technical image quality on 35mm. The only dynamic range advantage for medium format that should exist thanks to the format is the fact that the sensor area is 2.5 times larger, which means 2/3 stop less photon shot noise. The rest is due to differences in quality in the electronics, where many MFDBs seems to have a considerable advantage over say 5Dmk2.
It is commonly claimed that it is claimed that MFDBs are *several stops* better than DSLRs but I'm a bit skeptical about that. I'd like to see a comparison with properly expose-to-the-right D3x for example. To make it really tough competition you could boost the D3x with a color filter on the lens to balance the green channel :-). Eric's result of 3 stops between 5Dmk2 and the best MFDB seems very plausible though, due to the line noise problem.
Concerning fine differences in quality the buyers generally care much less than the experts, that is the photographers themselves. Picture content is always most important of course, but it does give an extra dimension of satisfaction if I know that also the technical quality is top notch. But people are different in this regard, and I guess it is probably a lot healthier not worrying so much about the technical quality :-).
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James,
These are good points, and agreed, its great that digital tech has gotten to the stage where we can put our energy into thinking about lighting or somewhere else entirely. For me that means I spend a lot less time trying to fix images in PS. I can't really tell much about skin tone from your shot, not any more than the three images I've attached. ;)
One from each camera.....canon 5d2, p20, CF528c
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All the talk about pattern noise and false ISO, read noise, blah blah blah is fine, but look at the photos coming from Libya, Afghanistan, Yemen. Beautiful images, inspiring. Mainly shot with 5D2s.
Amen to that.