The GetDPI Photography Forum

Great to see you here. Join our insightful photographic forum today and start tapping into a huge wealth of photographic knowledge. Completing our simple registration process will allow you to gain access to exclusive content, add your own topics and posts, share your work and connect with other members through your own private inbox! And don’t forget to say hi!

The 9 micron sensor: Magic or Myth?

Jack

Sr. Administrator
Staff member
We got into a partial discussion surrounding the different "looks" generated by the different sensors we were comparing in the P65+ sneak peek thread (see here: http://forum.getdpi.com/forum/showthread.php?t=4333). A few folks commented on how the P25+ files with their "fatter" 9 micron pixels appeared to generate an image with more "pop." This is a fairly common reaction to 9 micron sensors from any of the manufacturers and most of us who look at a lot of digital files do see it, myself included. So I decided it might be worthwhile to start a thread about it where we can share some theories.

I say theories, because in trying to get my arms around the technical and mathematical aspects of cross-comparing many of the factors I believe contribute -- such as total DR, inter-pixel-contrast, Nyquist limits and lens performance -- I quickly realized I was going to have make too many assumptions to nail anything down in a concrete fashion. Moreover, I "see" what folks are talking about, so I know it is a "real" trait from that standpoint -- and can therefore look at it empirically. That conflicts with the mathematician-engineer in me, but is perfectly suited to my inner-artist, and since empirical is easier to compare visually, my inner-artist won out over my inner-mathematician :D. Here is an overview of some image comparisons I performed -- I used the series of "Across the Lake" test shots we already showed in full and crops from in the main thread.

Note these are my theories, observations and conclusions and presented here only to start the discussion -- I am *not* claiming them as facts.

For the first set of trials, I opened the three files that were as identical in framing as possible in C1 (4.5.1). My goals were to get the files as close to the same WB and overall color as possible, get them as close to the same exposure as possible, get as similar an inter-pixel appearance when viewed at 100% as possible and get the deepest blacks to the same point. This was attempted ALL in the raw converter, then the files were processed as 16-bit Profoto Tiffs for later working in Photoshop CS4 to finish the task. To accomplish the similar look, here is what was required in C1: I first matched WB as close as possible. The P25+ and P45+ were virtually identical when I was done, but the P65+ has a distinctly different color balance, so it only kind of close. Next I equalized local contrast (clarity) -- it is pretty obvious the P25+ has the most -- which required adjustments to the P45+ and P65+ files. In C1 I added 8 points clarity for the P45+ and 12 points for the P65+. Note that clarity also affects total contrast, and at this point most of the differences in perceived DR have evaporated from the files... Next I adjusted highlight exposures to the same level as the darkest image, in this case, the P25+. (It is important to note that none of the files had clipped highlights so I could have alternatively increased the two darker to match the lightest, P65+, but the slightly darker file showed better overall saturation, so I went that way.) I decreased the exposure on the P45+ file by 0.2 stop and on the P65+ by 0.4 stop. Finally I ratcheted the deepest black in the image to the same point in all three files. This required a minor levels adjustment to the each file -- I moved the black slider from zero to 6 on the P25+ file, zero to 4 on the P45+ file and zero to just 1 on the P65+ file. (Ironically, my gut tells me this indicates the P25+ may actually carry slightly MORE total DR than the other two backs!) At this point all of the images look very, very close save for a slight color difference in the P65+ and slight saturation differences (which I correct for in CS4 as explained below).

Once in CS4, I balanced saturation. I did it here because there was some differential saturation in the P65+ file I knew would get equalized by a vibrance adjustment, and C1 does not contain a vibrance slider as does LR/ACR. Here a 10 point bump in vibrance combined with a 10 point bump in saturation was given to the P65 file. The P45 got a 6 point bump in saturation only, and now all three files had pretty similar overall saturation. I then uprezzed ALL of the files to 24"x32" prints at 360 PPI. This required only a marginal 50% uprez on the P65+ file, but a significant 400% increase on the P25+ file. My goal here was to have ALL files uprezzed at least some amount, as we might do with each file in a real-world example for a larger print. The advantage of uprezzing to a print size of 24x32 at 360 PPI is it also serves double-duty as an identical print file for doing a 36"x48" print at 240 PPI.

The one thing that is very difficult to show online is how prints look comparatively. What I have found is that you can get a reasonable approximation of how final prints will compare by viewing the files side-by-side at 50% view in PS. This I did do and grabbed a screen-shot of all three "crops shown onscreen side-by-side. This is a full-screen cut off my 30" display, so is a large jpeg. I am linking to it instead of embedding it here, click on the thumbnail. You can easily tell which image is which by reading the titles. Note that these are *NOT* sharpened for output yet, but may show some jpeg compression artifacts:



~~~

A summary of my observations viewing all of these onscreen:

1) First, I feel I did get the 9 micron "look" in the other two files using my set of adjustments. IMO I would thus call the myth "busted," though admittedly I feel the 9 micron sensors deliver the better look without added work, so maybe there is something to the "magic" side.

2) You can definitely see the progressive additional detail as we move up in sensor resolution at 100%, but they are pretty slight and diminish to almost insignificant levels in the 50% view.

3) The P25+ has a propensity to generate visible moire in areas of repetitive fine detail like the mini-blinds in the windows seen in the screen capture. I conclude this tends to happen most often when the lens is sharper than the sensor, but also suspect the lens being sharper than the sensor is paramount to why the 9 micron sensors exhibit more inter-pixel contrast without added adjustments. Pick your poison.

4) The P45+ and P65+ 50% views are very, very close to my eyes, with an ever so slight advantage to the P65+ in the areas of really fine detail like the individual willow leaves, blades of tall grass and thinnest branches on the bushes and trees. Here the P25+ looks a bit softer for sure, but still resolves most of these same detail parts as well-defined individuals. I conclude here that the minor differences between the P45+ and P65+ may be because we are very near the limit of lens resolution already in the P45+.

Now for my summary after viewing actual prints.

1) In the 24x32 inch prints, the difference in discernible detail is IMO insignificant. In fact, I can only detect actual detail differences by viewing the print with a loupe. Using my reading cheaters at 12", I cannot see any significant differences -- really!

2) In the 36x48 inch prints... Here, with my nose in the prints, I can detect a slight loss of detail in the P25+ print -- it is very minor, but it is visible. However, it is not really noticeable unless you are comparing the P25+ directly to one of the others with your nose in the print. Between the P45+ and P65+, I see no difference. Again, if I use the loupe, I can see a slight edge to the P65+ print -- but even then it's a very tiny difference. From this observation I conclude the P25+ is starting to hit a limit on critical (very critical) detail at 36x48 inch print sizes. As photographers, I feel we are generally far more attuned to the minor nuances of detail than "normal" art viewing folk, so no doubt the P25+ could still go twice that large for most normal viewing situations.

3) Moire in the P25+ (not sure it carries through to other 9 micron pixel backs, but I assume it does) is a real issue and the user needs to learn/know how to deal with it. Note that the C1 software DOES contain a moire reducer (don't know about the others), but I did not run it for this test as it also kills very fine detail. My solution would be to run two conversions of the same file, one with and one without moire reduced, then layer them in CS and mask out the offending moire areas -- in this way the final image maintains the best from both conversions. Alternatively, if the uber-fine detail is not relevant to the image -- which in all honesty it often isn't -- then by all means save the masking hassle and use the moire tool (if available) during raw conversion.

A final thought: If you are regularly going to print larger than 24x36, then for sure the smaller pixel backs are probably worth looking at for their added ability to render very fine detail. However, understand you may become "lens limited" quickly and may need to consider an alternative camera system with digital-specific or high-resolution lenses to fully utilize the resolution the back is capable of.

Cheers,
 

lance_schad

Workshop Member
Wow great report Jack.
I really liked the methodology along with the multiple print examples.
I am sure the readers will be enlightened by it.
I am glad that I was able to assist because it is hard to actually get all three backs for an evaluation like this in the same place with more importantly same camera position/type.
Looking forward to hearing some other observations.
L
 

tashley

Subscriber Member
Phew, Jack, that was an astonishing marathon of really useful information. I can't begin to question your methodology or conclusions: I'm simply grateful for them!

Tim
 

mark1958

Member
Jack great piece of work. Was the moire result reproducible in multiple images? I had seen moire with my leaf aptus 65 that I did not see with my hasselblad H3DII and 35mm HC. In addition, I would say that my Leica 28mm R gives moire on my 1DsmkIII. In that case, I always thought it was possibly due to the adapter and the distance of the lens mount to the sensor being slightly different than what you normally get with a canon lens. If your theory is correct, perhaps it is due to the greater resolving power of the leica glass. However in that case more variables. I guess based on your data no need for the P65. M
 

fotografz

Well-known member
That's the longest post I've ever seen you write Jack ... and I read it all because he subject is indeed intriguing.

I do think that you are right in concluding "bigger isn't always better." However, it's a difficult pill to swallow because we have been hard-wired to believe the opposite.

What I find terribly interesting is how the backs started, and where they have migrated to in terms of application .... and the questions of appropriateness that may arise.

We forget that these were (and may still be?) primarily studio solutions. ISO selections other than 100, on board LCDs and CF card capture are relatively recent additions. Most backs were tethered to stationary cameras/computers shooting with powerful strobes. Even the first "portable" Kodak ProBack I owned still needed a huge Quantum battery, and only worked on a 555 ELD Hasselblad and my giant RZ Pro-II with a very expensive Kapture Group adapter. Portable it wasn't, in the current sense of the word.

Then came the Kodak ProBack 645 which @ $12,000. set the industry on it's ear. Totally portable, (and still the model for many MF digital back solutions.)

Back to the studio scenario ... it is here that the higher meg backs come into their own. When shooting available light outside, my 9 X 9 micron sensor CFV with legacy V lenses is fabulous ... move into the studio with all that sparkling and well controlled light, and it's still very good, but not so fabulous. The 39 meg back sings here. But as you say, it sings best with APO view lenses. I rarely use the 39 camera because the back is on the Rollei Xact 90% of the time.

Lastly, IMO, we tend to forget how images are viewed ... only other photographers press their noses against the image and whip out their Sherlock Holmes magnifier. People take it all in as a holistic experience .... and, besides content which is the most important aspect of the experience, color, tonal gradations, and the "impression" of clarity play a huge part in the overall emotional reaction to an image.

Just a few random thoughts.
 

Guy Mancuso

Administrator, Instructor
Well let me add Jack and I have talked at great length on this subject and last week we came to some of these conclusions and today on the phone he was describing all of this in print. I found his testing and such dead on in regards to what we already talked about with a few surprises on how well the P25 Plus holds it's own. Now as a owner of the P25 Plus I can address the moire issue as i have said in the past it is there and sometimes it is there often. It maybe the only issue i have seen with this back and I would assume other Kodak backs. Dalsa sensor backs i can only comment on the ZD which had the Aptus 22 inside it and i do remember moire but maybe not as frequent as my P25 Plus but obviously I had this back longer and shot a lot of many different subjects with it. Yes the Moire tool works and i have used it in C1 with great success and also even have a action for it. Now normally it shows up mostly with clothing which includes people so any softening with the Moire tool is not a big issue but when it hits window blinds and tile roofs than to get around it faster i use the Moire tool to rid the problem than sharpen a touch more than my base settings or I can do the masking as Jack describes. i will say if I shot fashion or clothing all the time I may have chosen or would maybe use a P30 plus or the P45 Plus . Micro lenses tend to be less a moire issue with the P21 plus and P30 plus at least from what I have seen it seems the case even though Micro lenses are not directly supposed to be related to moire reduction. It maybe a simply case of the smaller micron sensor and that is something we would have to test for to be sure. If we have DMR and or M8 shooters some of this comes through with those units as well. I have had both and run into several times. I will say the P25 plus may have more or it comes up more but at the end of the day it does not bother me because it is a easy fix and the workarounds are very simple and in C1 if you have a bunch of images of the same type than you can simply copy the settings from one and apply to others as well in a key stroke. Bottom line this is the price to pay for non AA filter camera's or backs. I accept that with open arms since i hate AA filters and there results from them.

Jack excellent report my friend, just great stuff.
 

Jack

Sr. Administrator
Staff member
Thanks for the kind words guys, and I'm impressed with you who taking the time to read it all! :ROTFL:

Mark: Yes, the moire was reproducible and more common with the P25, but only with the best lenses mounted and in image areas containing high-frequency detail.
 

jlm

Workshop Member
i find that medium format, the viewfinders and results suit my way of working just fine with the CFV or now, the P20. i do see more ducks in the 65 shot however;)

yesterday though i picked up a Lumix G1 and that baby for $700 has some features that should embarrass all the MFDB makers...like the live view and the amazing manual focus function, a histogram showing while taking the shot and the so convenient, high quality, positionable LCD screen. really shows what could be done to improve functionality
 

Guy Mancuso

Administrator, Instructor
That is one cool little camera John. I played with one for about 2 hours and it was just fun to shoot.
 

mark1958

Member
Jack.. I guess it would be interesting to see how the 65, 45, 21 compare against some of your view camera digital lenses.
 

Dale Allyn

New member
Jack,

I really appreciate this report, and the effort it took to compile it. Very practical info indeed. For me, the buck stops at the print (not peeping at files) and the fact that you saw this through to paper and ink lends so much more substance to the discussion.

All of this discussion and shared experience supports what conclusions I was beginning to come to, in that if one is to move up to the P45+ and P65+ backs s/he must also plan to give it the best glass. For me, the differences we're seeing between the P65+ and P45+ are not enough to make me hunger for the P65+... unless going for massive prints of images captured with the more specialized lenses (e.g. Schneider or Rodenstock optics, etc.). The P45+ (or other 39MP sensors) seems to be a sweet spot, with the P25+ holding up quite well. I'm very happy with the P25+ and your report adds even more support for that contentment (for now).

I'll also repeat my appreciation to the folks at C.I. and Phase who helped to make this comparison possible.

Cheers!
 

fotografz

Well-known member
RE: Moiré

dual process the file with and without moiré filtration, layer and paint out the bad effects.
 

LJL

New member
Jack,
Very nice, detailed presentation and description of file treatment and thoughts about stuff. I would agree with your comment about the "myth" being busted, but maybe the "magic" remaining to some degree.....if I really thought the output from the 9x9 micron stuff was truly mythical ;-) Aside from the color variances you mentioned with the P65+, these results are demonstrating that the P25+ does hold its own quite nicely (despite moire issues), and the P45+ interestingly to me looks like it does land between the other two....color still seems just a teeny bit soft compared to the P25+. (The reds on the dock are my focus point here. To my eyes, there may still be a bit more black in the P25+ shot than the others, as the reds have a bit deeper/richer look. I know this is really splitting hairs, and as you say, nobody is ever going to tell them apart unless looking side-by-side-by-side.....and then make them "justify" what they think they are seeing.)

Guy,
You may want to hold on to that P25+ back, as I mentioned to you before. It is definitely holding its own for these kinds of outdoor/landscape type shots. Really more than "acceptable". It does produce some very nice files.

Marc,
I really think you are onto that other key point....the P65+ and probably the P45+ backs will do well in this landscape setting, but they will dazzle under the controlled studio lights....maybe more than the P25+ in this case. That could be the next iteration comparison....do them together under Elinchroms, Hensels, Profotos, Brons, or whatever one wants to use. I would guess, as you comment, that the bigger backs will really shine in that setting.

This is really nice to see, and frankly, it should help a lot of folks better understand what may or may not be going on, which is "better" or not, which may fill most needs, etc. Since the body, glass, set-up, etc., was out of the equation, and the processing was genuinely done to get as close to parity as is reasonable, AND the PRINT was actually part of the equation, it should be viewed as more than "fair" in comparisons.

Great stuff. Thanks to all involved with this effort.

LJ
 

EH21

Member
Jack,
Looks like you did a lot of work, however hate to say your test is near meaningless without using a scientific study that can provide quantitative results - something like Imatest to accurately check Dynamic range, Color accuracy, and sharpness. Sure you can see stuff like Moire and also that the p25 is picking up more detail in the shadows - look under the house for example. (But one would expect the p25 to have more DR as the kodak technical website specs it out as having more.)

Your test overlooks something important for a lot of shooters - diffraction. One would expect the smaller sensel chips to see diffraction limits at larger apertures than the 9micron chips. This is a really important test for people shooting landscapes and products that need big DOF.

Another area where I'd expect to see differences in these backs is that the newer Kodak chips have different color filters which should allow for better color accuracy. No way you are going to see this on a monitor with the kinds of tests you are doing. Imatest will give you the deviation vector for all the chips on your color chart in like 5 minutes worth of work. Same for DR.

There may be other programs out there besides Imatest, but that's what I've used and it's extremely accurate and much easier to get reliable results.

Then later down the road you can come back and test something else and make a fair comparison instead of judgement calls which don't do anyone any good.

Best of luck,
Eric
 

Dale Allyn

New member
Jack,
Looks like you did a lot of work, however hate to say your test is near meaningless without using a scientific study that can provide quantitative results - something like Imatest to accurately check Dynamic range, Color accuracy, and sharpness. Sure you can see stuff like Moire and also that the p25 is picking up more detail in the shadows - look under the house for example. (But one would expect the p25 to have more DR as the kodak technical website specs it out as having more.)

Your test overlooks something important for a lot of shooters - diffraction. One would expect the smaller sensel chips to see diffraction limits at larger apertures than the 9micron chips. This is a really important test for people shooting landscapes and products that need big DOF.

Another area where I'd expect to see differences in these backs is that the newer Kodak chips have different color filters which should allow for better color accuracy. No way you are going to see this on a monitor with the kinds of tests you are doing. Imatest will give you the deviation vector for all the chips on your color chart in like 5 minutes worth of work. Same for DR.

There may be other programs out there besides Imatest, but that's what I've used and it's extremely accurate and much easier to get reliable results.

Then later down the road you can come back and test something else and make a fair comparison instead of judgement calls which don't do anyone any good.

Best of luck,
Eric
Eric,

To say that Jack's report of his observations are "near meaningless" is an admission to having not read his original post with an open and considerate mind IMO. Perhaps they have little meaning for you, but that's not the same as "meaningless". As I read it, Jack did not post that his statements constitute theorem, but a theory, or even more so, personal observations. And furthermore, it appears that your interest is more intended towards a technical pissing-contest than a mutually beneficial conversation about a few of the digital backs available to us. Information in this thread seems geared toward practical, useful comparisons of available equipment in "real world" situations as they relate to a specific type of photography (as sampled). It does not appear to attempt to cover all situations. It is a conversation.

Your remarks regarding diffraction are valid and they do apply to certain applications (mine in particular), but that does not render Jack's (et al) observations invalid as you imply in your post. Why not contribute useful additions to the process rather than attempting to render someone else's contributions less useful to the group? A "winner" is not sought here, but shared growth is. Arrogance is the bane of internet fora, and an obstacle to shared learning and advancement.

Regards,

Dale Allyn
 

fotografz

Well-known member
IMO, in the end it IS subjective judgement regardless of scientific nit picking.

Obviously, photography is dependent upon science for it's very invention and existence ... and most certainly is an evaluative discipline to discover why something "is, or is not."

However, that aspect comes into play when subjective observation tells it to ... both for invention and for evaluation. I take it that Jack's post was done because many people have subjectively observed that the larger pixel pitch backs have "something" going for them that's logically hard to explain but relatively easy to see.

I've been doing photography for more years than I am willing to admit ... and one thing I've noticed is that we are a mixed lot ... many scientific minds with a creative streak, or "creative types" with some scientific curiosity.

With the advent and proliferation of digital, the balance has decidedly shifted to science, and the debates gather and disseminate huge amounts of data in support or denial of subjective observation.

My gripe is that subjectivity is generally becoming easy to dismiss with an overwhelming scientific tongue lashing. Yet in practice, I feel that clinical correctness has sucked the joy out of the creative process and subjective discovery. So many people are preoccupied with scientifically justifying and debating, that their inner child has been bound and gagged ... and they don't trust their own observations anymore.

I personally do not need to scientifically quantify my creative and subjective observations. I like occasionally reading those from others, but have, and will always trust my eyes in the end ... and embrace all the discriminatory creative prejudices inherent in that very personal creative process honed over the years and years of observing.

"I like, I don't like" ... and really don't give a healthy dump as to scientifically "why". The why is boring to me. I leave the "why" to nit pickers who derive joy from dissecting every pixel until it's all cataloged and neatly placed in it's proper column on the spread sheet of their minds.

In reality, I bet a 22 meg back will fulfill the requirement of 95% of most people's "real" needs. As Jack concluded, if you produce huge prints or shoot for excruciating detail, then up the game with both a bigger back and all other stuff you need to make use of that increased resolution. IMO, it's somewhat common sense.
 

Paratom

Well-known member
Are you saying its more relevant what is measured compared to what can be seen?


Jack,
Looks like you did a lot of work, however hate to say your test is near meaningless without using a scientific study that can provide quantitative results - something like Imatest to accurately check Dynamic range, Color accuracy, and sharpness. Sure you can see stuff like Moire and also that the p25 is picking up more detail in the shadows - look under the house for example. (But one would expect the p25 to have more DR as the kodak technical website specs it out as having more.)

Your test overlooks something important for a lot of shooters - diffraction. One would expect the smaller sensel chips to see diffraction limits at larger apertures than the 9micron chips. This is a really important test for people shooting landscapes and products that need big DOF.

Another area where I'd expect to see differences in these backs is that the newer Kodak chips have different color filters which should allow for better color accuracy. No way you are going to see this on a monitor with the kinds of tests you are doing. Imatest will give you the deviation vector for all the chips on your color chart in like 5 minutes worth of work. Same for DR.

There may be other programs out there besides Imatest, but that's what I've used and it's extremely accurate and much easier to get reliable results.

Then later down the road you can come back and test something else and make a fair comparison instead of judgement calls which don't do anyone any good.

Best of luck,
Eric
 

Guy Mancuso

Administrator, Instructor
IMO, in the end it IS subjective judgement regardless of scientific nit picking.

Obviously, photography is dependent upon science for it's very invention and existence ... and most certainly is an evaluative discipline to discover why something "is, or is not."

However, that aspect comes into play when subjective observation tells it to ... both for invention and for evaluation. I take it that Jack's post was done because many people have subjectively observed that the larger pixel pitch backs have "something" going for them that's logically hard to explain but relatively easy to see.

I've been doing photography for more years than I am willing to admit ... and one thing I've noticed is that we are a mixed lot ... many scientific minds with a creative streak, or "creative types" with some scientific curiosity.

With the advent and proliferation of digital, the balance has decidedly shifted to science, and the debates gather and disseminate huge amounts of data in support or denial of subjective observation.

My gripe is that subjectivity is generally becoming easy to dismiss with an overwhelming scientific tongue lashing. Yet in practice, I feel that clinical correctness has sucked the joy out of the creative process and subjective discovery. So many people are preoccupied with scientifically justifying and debating, that their inner child has been bound and gagged ... and they don't trust their own observations anymore.

I personally do not need to scientifically quantify my creative and subjective observations. I like occasionally reading those from others, but have, and will always trust my eyes in the end ... and embrace all the discriminatory creative prejudices inherent in that very personal creative process honed over the years and years of observing.

"I like, I don't like" ... and really don't give a healthy dump as to scientifically "why". The why is boring to me. I leave the "why" to nit pickers who derive joy from dissecting every pixel until it's all cataloged and neatly placed in it's proper column on the spread sheet of their minds.

In reality, I bet a 22 meg back will fulfill the requirement of 95% of most people's "real" needs. As Jack concluded, if you produce huge prints or shoot for excruciating detail, then up the game with both a bigger back and all other stuff you need to make use of that increased resolution. IMO, it's somewhat common sense.
Well said . My clients are looking at reality and not the science of it. I can't sell a Imatest result. For me i will go what looks the best 100 percent of the time. The issue is lens testing never shows what the look of the lens actually does or what the final results look like. Tests are great for some things but in the end we sell results or print results for the wall or clients needs.

Also one issue right now is we can't test the P65 for color and noise floor since the firmware is NOT correct and it is off right now and we are talking to Phase about our testing and the needed final firmware for shipping.
 
A

asabet

Guest
We got into a partial discussion surrounding the different "looks" generated by the different sensors we were comparing in the P65+ sneak peek thread (see here: http://forum.getdpi.com/forum/showthread.php?t=4333). A few folks commented on how the P25+ files with their "fatter" 9 micron pixels appeared to generate an image with more "pop."
In any size format, from small sensor to medium format, there always seem to be similar schools of thought, that the fatter pixels produce an image with more pop. From what I have seen when tests are done properly, such as yours were, the results are always in line with what you found. Nothing magic about larger pixels in terms of crispness or pop. With a given high quality lens, a greater number of smaller pixels gets you a little more resolution and a little less moire. The idea that the fat pixels hold some magic in this regard is probably rooted in a subconscious impression that comes from viewing the pixels onscreen at 100%, where the fat ones look crisper.

The two areas in which I'd expect that fatter pixels may hold an advantage are dynamic range and colors. These were not the focus of your test though.

As for Eric's comments about diffraction, I think it's worth pointing out that diffraction limits are never a weakness of a sensor, but a property of the optics. A small pixel sensor is diffraction-limited at a lower f-stop only because a fatter pixel sensor is unable to "see" the effects of diffraction at that f-stop. Diffraction never causes the higher res sensor to resolve less than a lower res sensor with a given format size and lens.
 
Top