I only have first hand experience with my 5D and the 40D that I used to have, so I can't compare it to other cameras with sensors having a more similar pixel density.
But as you said, with the ZM25 the lens should not be the limiting factor. Even though the pixels are small, why should they be soft? Poor processing/NR even at base ISO? Or simply a strong AA filter (or diffraction but I'd think you didn't use f/16 for your tests).
Let me ask this: many people, yours truly inclided have been bitterly disappoinnted byt he Sony 16mm f:2.8 E-mount prime. The issue is extreme corner softness, extending far beyond the corners. How could Sony release such a dud, many of us wonder, particularly as primes are normally IQ territory.
Second element: on my NEX5, wide M-mount lenses result not only in colour shift, but also in extreme corner softness...
Third element: NEX C3 does not suffer from corner problems. Neither colour shift nor extreme softness.
This begets the question: what if the issue with the 16mm were not the lens but the interaction with the sensor? Which would suggest that this self same lens might interact quite a bit better with the C3.
So, what say you?
I'd say that's a possibility, Phillipe, although I'm not sure that we have much data on if and how much sharper lenses are in the corners with the new camera. I certainly hope you're right.
AhamB wrote:
I only have first hand experience with my 5D and the 40D that I used to have, so I can't compare it to other cameras with sensors having a more similar pixel density.
But as you said, with the ZM25 the lens should not be the limiting factor. Even though the pixels are small, why should they be soft? Poor processing/NR even at base ISO? Or simply a strong AA filter (or diffraction but I'd think you didn't use f/16 for your tests).
You mean why a 20 megapixel medium format back has higher per pixel quality than a 20 megapixel P&S? Well, because when you jam the photosites close together you run into a bunch of problems due to various forms of interference and because of the smaller well capacity.
After several years of buying new products with ever-higher pixel counts in the digital still-camera market, the average consumer equates the number of “megapixels” with image quality. Shrinking sensor pixel size, however, poses significant challenges to sensor design. As pixel size gets smaller, the well capacity shrinks, resulting in less dynamic range. The photon collection area also shrinks, causing less sensitivity. Noise, coupling, and nonuniformity become more severe and visible. The pixel crosstalk also inevitably gets higher.
Crosstalk occurs when photons falling on one pixel are “falsely” sensed by other pixels around it. For example, we call it crosstalk if we shine highly focused light only on a red pixel, and the blue pixel shows a response. In this extreme case, the blue channel response will be too high and skew the real pixel color...
....
crosstalk always degrades the spatial resolution, reduces overall sensitivity, causes color-signal mixing and, consequently, leads to image error after color correction....Show more →
One of the things I miss from using a DSLR are doing various shots taking advantage of interesting bokeh. With the M9 you have no idea of what the bokeh will look like until you actually take the shot - which makes compositions using the OOF rendering as an element impossible. The NEX-C3 allows me to do that and this time with Leica glass.
I really like to be able to do that. The flip side is that the crop sensor makes it essentially impossible to get that special look usually associated with medium format cameras but which can usually be approximated with a 35/1.4 on 35mm FF. You know what I mean - the subtle separation of foreground and background that makes the subject pop.. A few random examples of the effect:
On the positive side is that AF is very quick. I think that this generation of contrast based AF is actually getting comparable to consumer DSLR performance. Too bad that the current selection of lenses for the NEX is so underwhelming.
In order to reproduce 35mm f/1.4 on APS-C - you would have to attach ~24mm f/1.
And of course even that would not guarantee 3D, pop-up effect.
When you attach 35mm f/1.4 - you get results comparable to ~50mm at f/2.
Soon,
Sony is to release Zeiss lens for NEX - 24mm f/1.7. It will give results comparable to ~35mm at f/2.5.
There is one more difference to rangefinder lenses - shorter minimum focusing distance.
If someone wants to experiment - you can try to attach M lens to NEX and put MACRO close-up lens.
denoir wrote:
There's not theoretical possibility that any lens will make a difference, as I've already shown the results with the ZM 25 - the world record holder for resolution (>400 lp/mm MTF10). It's diffraction limited at f/4 i.e it has reached the theoretical optical maximum. And as sebboh points out there is no way a filterless camera can be matched in per pixel sharpness to a filtered one. So unless I botched the test somehow the only way that there could be a difference is if I put a really good lens on the C3 and a really crappy one on the M9 (the 28 Cron does not fall into that category) or if I botch the second test.
Making a mistake during such a test is of course possible, but unlikely as I'm using a tripod + timer release in both cases and use 15x live view focus on the C3. Furthermore I'm using wide angles so missing focus at/near infinity is extremely hard.
M9, ACR. C3 IDC. I can't be bothered to do the C3 image in RPP as I then have to copy files to my Mac laptop, but you've seen the improvement that RPP brings in the test a couple of posts back....Show more →
the m9+28cron combo looks really sharp. do you have anything in the 50mm range to try on a m9 vs the nex with 28cron. i am just trying to get an idea of how much per pixel sharpness there really is with these 2 cameras or maybe i just like to make you take more of these sample pics
kahren wrote
the m9+28cron combo looks really sharp. do you have anything in the 50mm range to try on a m9 vs the nex with 28cron.
Look a few pages back and you'll see a 35 v 50 test.
i am just trying to get an idea of how much per pixel sharpness there really is with these 2 cameras or maybe i just like to make you take more of these sample pics
Don't worry, I have no intention of doing more tests for you
Jerry_R wrote:
Soon, Sony is to release Zeiss lens for NEX - 24mm f/1.7. It will give results comparable to ~35mm at f/2.5.
Latest rumour was that it would become a 24mm f/2, probably because people are screaming for small (pancake style) lenses to go with the small NEX cameras.
AhamB wroteLatest rumour was that it would become a 24mm f/2, probably because people are screaming for small (pancake style) lenses to go with the small NEX cameras.
No, it is a mistake - old Sony presentation (with f/2) poped-up on Chinese forum.
I am really surprised how soft the images from C3/ZM18 combination compared to M9/Cron ! My 5D2 and Telyt 4/280 (also diffraction limited) images look much sharper and closer to M9/Cron image than the C3 image. If I were to hazard a guess, the pixel size in C3 should be in the range of ~ 4.5um, ~ 6um for the 5D2 and ~ 6.5 um for the M9. Which means, theoretically, C3 should diffract around f/5.6 - f / 7.1 ish range and slightly higher f/# stop numbers for M9.
Ajay C wrote:
I am really surprised how soft the images from C3/ZM18 combination compared to M9/Cron ! My 5D2 and Telyt 4/280 (also diffraction limited) images look much sharper and closer to M9/Cron image than the C3 image. If I were to hazard a guess, the pixel size in C3 should be in the range of ~ 4.5um, ~ 6um for the 5D2 and ~ 6.5 um for the M9. Which means, theoretically, C3 should diffract around f/5.6 - f / 7.1 ish range and slightly higher f/# stop numbers for M9.
What f/# did you use to shoot these images?
I think the RAW converter is at fault. If you look a few pages back you'll see that RPP does a much better job.
A Zeiss 24 mm f/1.7 lens would be superb, and hopefully it would have AF too. 