Thanks Erik, we love pixel peeping !!!
Hi,
MFDB_vs_DSLR2 page updated with a new pair of images (aspen with autumn leaves):
http://echophoto.dnsalias.net/ekr/Articles/MFDJourney/RawImages/MFDB_VS_DSLR2/
Best regards
Erik Kaffehr
I think your comparisons would work better as animated gifs ;)
Hi,
"the P45+ is a tiny bit sharper viewed at 25cm."
Best regards
Erik
... I could see for a fact that on the P45+ shot with the high peaks in the background and the wooden shack in the foreground the lens was focused on the foreground grass and flowers. That made everything else behind that much softer. On the Sony shot everything is more in focus...
... mostly intended for those interested about finding out about MFD image quality.
Probably DOF difference between formats, not focusing issue.
If you stop down to much diffraction takes a bit of the sharpness.
Erik, I think you are risking the fate of the guy who overheard medieval scholastic philosophers' attempts to determine, theoretically of course, the number of teeth in a horse, and dared to suggest to just open the horse's mouth and count. They beat the crap out of him for being so unsophisticated. Challenging dogmas with empirical results is always a risky proposition ;)
Regardless of what marketing would have us think, those resolutions are fairly similar to start with anyway.
If you need something significantly better, stitching is, and has been for years, the only option. ;)
When the second hand betterlight back I purchased finally clears customs in Tokyo, I may do some comparisons with the D800 and stitches. I am pretty sure that the D800 will come on top from a pure image quality standpoint, but we will see. ;)
I have managed to put together for a reasonable price a very nice portfolio of top notch second hand LF lenses in apparent like new condition (Schneider Super-Angulon 72mm f5.6 XL, Fujinon SWD 90mm f5.6, Rodenstock APO-Sironar Digital 150mm f5.6, Rodenstock APO-Sironar S 210mm f5.6 and Nikkor M 300mm f9). It will be interesting to see how they perform and whether focusing on my Ebony 45SU is accurate enough to be able to tap into their potential. As a side comment, all these lenses combined cost me only just a bit more than the price of a new Hassy HC 80mm f2.8 according to the new Hasselblasd price list (http://photorumors.com/2013/09/26/hasselblad-lens-price-increase-coming-on-october-1st/). ;)
Cheers,
Bernard
It has been suggested that you rent equipment for a few days, and find out. I had the P45+ for three months now, and I have still not found out.
.... The first exposures confirmed that it destroys any DSLR...
Then that is how one knows it is close between those two in landscape situations no doubt about it. The Sony produces a very pleasing file indeed.
That is why I stretched out by budget a bit and went with the 60MP IQ160 and Arca/Rodenstock lenses. The first exposures confirmed that it destroys any DSLR I have used (that includes the D800E with zeiss glass and the 14-24mm and the Canon DSLRs with the best lenses also).
I think the P45+ shines in very long exposures from what I have seen and obviously in the studio. The PhaseOne/CaptureOne tethered workflow is also superb.
Comparing resolution is fairly easy, in fact the only aspect of image quality that medium format is still undoubtly superior at. There are other more subtle factors but they are more debatable.
To me the creative process of using a tech camera (of the flexible kind) is more important than superior image quality, although adequate resolution for fairly large prints is still important to me. And if I did feel like the files from my 33 megapixel back and schneider digitar lenses would be significantly inferior to recent DSLR gear I'd probably stress for an upgrade although I don't really need it for my work, it's just the sickness of comparing with what "everyone else has got" which I'm not immune to :-). For now I'm pleased with the quality though.
Yeah, in that crop example I see a difference too. Subtle but it is clearly there.
The Rodenstock HR lenses (I have the 40 and the 70) are really amazing and take the backs (I presume any back) to another level in regards to resolution edge to edge. Also like mentioned the technical cameras offer something different in regards to workflow in the field. The tilt capability helps a lot in getting the proper depth of field with the large medium format sensors. I have a lot of shots that would have been really mediocre had I used a medium format slr instead due to the limited depth of field. With the Arca I can use the lens at an optimum aperture, f8, and get very large depth of field by using tilt. This is a huge asset in Landscape and studio use. With the smaller medium format sensors like the one in the Leica S, the Pentax 645D and the P40/IQ140 it is not as necessary although it helps but with the larger sensors of the 50-60-80mp backs I honestly believe it is critical to have. I think that applies to the P45+ also.
I had not used medium format in basically ten years and back then it was with film (6x7) which I felt was a touch smoother in the depth of field transitions from focus to out of focus. (film grain helps). High resolution medium format digital sensors make it very obvious when focus and or technique is not perfect.
What I have found with my phase back is that im loving the tech camera workflow but I really like the color depth and malleability of the files. The shadow detail and color fidelity in the shadows is superb. I also love the fact that I can still make a great 30x40" print even when I significantly crop the image.
I now im looking for a printing solution that can fully do justice to those files. THIS (http://duggal.com/hdc.aspx) looks like a good product
I think you should do some further tests; the effects of diffraction are usually minimal compared to improper focus. Focus using the hyperfocal distance and stop down an extra 2 stops. From many years of experience shooting CF lenses diffraction has never been an issue. I recently spoke to a Hasselblad technician that seemed to think so as well stating that none of the CF lenses were ever diffraction limited.
Hi,
A lens that is not diffraction limited at medium aperture is not a good lens. I measured MTF on a Sonnar 150/4 and it started loosing sharpness at around f/11.
The best lenses usually are diffraction limited at f/5.6. That is probably the case with Rodenstock HR lenses. The Hasselblad guy you spoke with seems not so competent with regard to optics.
Diffraction is a property of light and not of lenses. Light passing trough a small hole bends, depending on wavelength and size of the whole. When you stop down the lens improves because aberrations go down with increasing f-number, diffraction increases. At a point the increase of diffraction dominates over the improvement, at that point the lens reaches optimum performance. Very good lenses reach this at larger apertures.
That said, diffraction is not always bad, it is benign to sharpening, as it can be approximated with a gaussian. Diffraction also helps reducing aliasing. Color aliasing sometimes goes away at f/16, or so, the reason is that you loose resolution/edge contrast.
Best regards
Erik
My whole point is that measuring MTF and using optimum f-stop is completely pointless if you can't properly focus the lens and get the required depth of field. In all my years shooting film improper focus and insufficient depth of field have always been more detrimental to image quality than diffraction.
The image you posted is improperly focused and doesn't have enough depth of field and you would improve your overall IQ by worrying less about diffraction.
| f/8 | f/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) |
My whole point is that measuring MTF and using optimum f-stop is completely pointless if you can't properly focus the lens and get the required depth of field. In all my years shooting film improper focus and insufficient depth of field have always been more detrimental to image quality than diffraction.
The image you posted is improperly focused and doesn't have enough depth of field and you would improve your overall IQ by worrying less about diffraction.
Hi, I downloaded the images and looked at the iiq files in C1Pro7 and all files on LR5.
The P45+ files do look softer. I think lens diffraction is in play. Did you shoot at f16? Either that or the lens quality and focusing is not up to snuff.
I could see for a fact that on the P45+ shot with the high peaks in the background and the wooden shack in the foreground the lens was focused on the foreground grass and flowers. That made everything else behind that much softer. On the Sony shot everything is more in focus. Also on the P45+ shot the light changed and all the foreground is in shadow (which could be brought up easily) and in the sony shot that same area is perfectly lit. That makes a huge difference.
Eric, Thanks for posting the comparisons.
I am curious what you found out on the Dynamic range between the P45+ and A99. My main issue with the P45+ over the years I shot it was that limited DR especially in the highlights area. I found that exposure bracketing was necessary most of the time. Shadow areas were somewhat recoverable, but if highlights were showing near to blown, odds are they were not recoverable. I also had trouble with the P45+ sometimes pulling out details in shadows, where details sometimes were smeared or not very clear. The A99 IMO should have the the edge in the DR area but it would be interesting to see your results.
I mainly used the Mamiya AFDIII, the DF with various Mamiya lenses.
Have you used yours on a exposure past 30 minutes yet. The P45+ has some amazing capabilities in the longer exposures. The only limitation I found was the 69F temperature limit for 1 hour and low humidity.
Paul Caldwell
Eric, Thanks for posting the comparisons.
I am curious what you found out on the Dynamic range between the P45+ and A99. My main issue with the P45+ over the years I shot it was that limited DR especially in the highlights area. I found that exposure bracketing was necessary most of the time. Shadow areas were somewhat recoverable, but if highlights were showing near to blown, odds are they were not recoverable. I also had trouble with the P45+ sometimes pulling out details in shadows, where details sometimes were smeared or not very clear. The A99 IMO should have the the edge in the DR area but it would be interesting to see your results.
I mainly used the Mamiya AFDIII, the DF with various Mamiya lenses.
Have you used yours on a exposure past 30 minutes yet. The P45+ has some amazing capabilities in the longer exposures. The only limitation I found was the 69F temperature limit for 1 hour and low humidity.
Paul Caldwell
My whole point is that measuring MTF and using optimum f-stop is completely pointless if you can't properly focus the lens and get the required depth of field...
Then do your own test with proper focus and DOF. Show us how it should be done. Sheesh!
Hi,
What I can see, the Alpha 99 has a wider dynamic range. In my view DR is essentially something that affects the darks. The idea is that you expose for the highlights, that is highest possible exposure without clipping highlights, than you handle highlights in postprocessing. The highlight slider in Lightroom is quite effective, past -50 it is said to kick in some local tone compression techniques.
Exposing for highlights makes for dark images. It is quite often I use a graduated filter in Lightroom, large amount of highlight compression and than increase exposure. In short, my recipe is:
- Expose for the highlights
- Use graduated filter in LR (or ACR) if possible with some negative exposure and excessively negative "highlights"
- Use highlights-slider aggressively
- Adjust exposure
- Use "blacks" slider to get some clipping in deep shadows if needed
- Readjust exposure
I often use "raw digger" to evaluate an image. The normal histograms are not very reliable.
The two enclosed images show the raw histogram from RawDigger indicating some clipping in the clouds and the original and processed image. If you use Capture One, try to use linear curve instead of film curve they have as default.
See this page for DR comparison between P45+ and Alpha 99, but be aware of the images not being comparable, DoF is different: http://echophoto.dnsalias.net/ekr/index.php/photoarticles/76-my-medium-format-digital-journey?start=8
I have also shot some tests with a Stouffer wedge, but those results were hard to interpret. How much is sensor and how much is processing? How much DR can you tweak from an image?
Best regards
Erik
Erik, thanks for the link. It seems to say in the histogram that the P45 has about 1 ev advantage over the Sony A99. +3 to -8 vs +3 to -7. It's also interesting that the slope of the darkest evs are completely different for the same shot.
On the picture, the P45 blocks up to black much faster than the A99 on the darkest tree trunks despite the 1 ev advantage. Any idea why that might be?
Then do your own test with proper focus and DOF. Show us how it should be done. Sheesh!
Erik, I'm referencing the flower and the shack. "I wanted the flower in the foreground to be sharp and have a decent depth of field. My focusing accuracy is not perfect."
If you want good depth of field you should not focus on the flower and instead focus somewhere between the flower and the mountains using the hyperfocal distance instead, and add 1-2 stops. I'm not presenting anything new "sheesh"... :-)
As for pixel peeping... I really think the issue of diffraction is exagerated. Yes it can be seen gluing your nose to the screen at 100% but in print it will hardly be noticeable. If you want sharp focus you should always give yourself enough depth of field by stopping down without worrying about diffraction. Obviously if you have enough depth of field at f8 then don't use f16...
As for the wavy field, it's another non-issue in the real world - and a non-issue in the studio "focusing on a model's eyelashes..." ;) ;) ;)
As for those three comparison shots with the yellow flower in the foreground something doesn't seem right. Have you had your body aligned and your lenses reset for infinity focus ? Often the foam for the mirror compresses or disintegrates and focus is off... I just had mine serviced and it makes a world of difference.
Since you have a digital back you can also take advantage of focus stacking...
My last piece of advice for taking better pictures... leave the 150 at home :)
Diffraction at f/16 gives an airy diameter of 0.021 mm so it limits sharpness more than DoF. So you say I should ignore diffraction and complain about diffraction in my image.
Your comment of focusing on the eyelashes is a bit comic
I shoot film and pixel peep with a 15x loop :)
as all the samples I have posted are landscape mostly at infinity. Many of yours also fall in the same category as far I know.
Have you published any raw images of your own? Would be interesting to see what is your reference of sharpness. The reason I published these results is that raw images from MFD are scarce.
That comment of yours on the 150/4 lens is what I would call stupid. Each lens has a place.It's not stupid; it's advice many photography teachers give their students (shooting wide and moving in closer to your subject).
I shoot film and pixel peep with a 15x loop :)
Wasn't it you who warned Erik about risking the fate of the guy who overheard medieval scholastic philosophers and getting his ass kicked ?!
;D
Erik, I'm referencing the flower and the shack. "I wanted the flower in the foreground to be sharp and have a decent depth of field. My focusing accuracy is not perfect."
If you want good depth of field you should not focus on the flower and instead focus somewhere between the flower and the mountains using the hyperfocal distance instead, and add 1-2 stops. I'm not presenting anything new "sheesh"... :-)
As for pixel peeping... I really think the issue of diffraction is exagerated. Yes it can be seen gluing your nose to the screen at 100% but in print it will hardly be noticeable. If you want sharp focus you should always give yourself enough depth of field by stopping down without worrying about diffraction. Obviously if you have enough depth of field at f8 then don't use f16...
As for the wavy field, it's another non-issue in the real world - and a non-issue in the studio "focusing on a model's eyelashes..." ;) ;) ;)
As for those three comparison shots with the yellow flower in the foreground something doesn't seem right. Have you had your body aligned and your lenses reset for infinity focus ? Often the foam for the mirror compresses or disintegrates and focus is off... I just had mine serviced and it makes a world of difference.
Since you have a digital back you can also take advantage of focus stacking...
My last piece of advice for taking better pictures... leave the 150 at home :)
Eric:
Love the meadow shot, where was that taken? Was that a wide Zeiss as your overall DOF looks very good. With the Mamiya's I was not able to get that type of coverage on either the P45 or IQ160.
Back on the processing, I think you already mentioned the Film curve vs. Linear curve in processing out in Capture One. I have often found that with the P45, the linear curve was much more forgiving especially on the highlights. You don't see the same pop in the file that that can be processed back.
Paul Caldwell