The contrast on the chart matters little, Imatest compensates for that.
I'm going to recheck the noise ratios on Sigma and ZD. The question is not about ISO, f-stop and shutter speed, but how far to the right the images are exposed.
My understanding is that you are feel that you got better detail on the ZD than on the D800. Checking with Imatest indicates the opposite, I have not really found any explanation. What is your take on the issue now?
I also checked the Nikon 50/1.4 and the ZD at 80/2.8, reason being mainly that I expect Mamiya with it's larger pixels being less affected by diffraction.
Regarding the Zeiss 24/2 sample, it was coming from Tim Parkin, I don't recall how it was "developed" but raw processing matters a lot. I'll try to check out about the sample. Right now I feel that it would be good to find out about the issue you have and not looking for the ultimate lens. The new Zeiss Distagon 55/1.4 seems to be a very good lens, but I think the price will be exceptional.
One of the reasons I am much interested in this that there are quite a few poster who claim that even old 25 MP backs are superior to todays CMOS based FF sensors. So I am very much interested finding out why and how.
Hi Erik, thanks for looking into these files.
For the noise comparison, it might be more accurate to compare files from Sigma @5.6 and Mamiya @5.6 as their raw exposures were very close.
D800e was at 100 ISO and ZD at 50 ISO.
The black square of the slanted edge was not a very deep black, but a dark grey (as came out of my laser printer).
I carried raw development using low contrast & linear base tonal curves, do you think results would be different if higher contrast files were used?
Comparing these findings vs the charts from 25/2 Zeiss Distagon on the Nikon D800E is Zeiss that much better?
I see that the contrast of the Zeiss chart is much higher (but this could be due to raw conversion setting), do you think it could be a factor?