Hi,
Thanks for the link!
Comparing FF on Alpha 900 and Nikon D3 certainly skews the result a bit because of the different pixel pitch. My impression of the first published results from the Alpha 900 was that the 24-70/2.8 is not sharp in the corners at f/8 and what I see here is similar. It seems that corner performance is optimal at f/11. Both the Nikon 24-70/2.8 and the Canon 24-70/2.8 seems to perform better at 70 mm. I now consider changing my preset three on my Alpha 900 from f/8 to f/11, my preset three is for critical shooting from tripod.
This is a bit consistent with my own testing, my Konica-Minolta 28-75/2.8 definitively outperformed the 24-70/2.8 at wide apertures at 70 mm on test charts, where the ZA performed very poorly. I see quite a lot of corner softness on my sample of the 24-70/2.8 at 24 mm although I think I have a decent sample because corners are pretty much equal. In actual use the ZA performs better than in my tests.
It is well possible that the observations are consistent with Zeiss design principles pushing for a large sweet spot with high contrast but requiring a lot of stopping down to get corners critically sharp. I got the impression that Zeiss designs are not really optimized for corner resolution from the writing of Lloyd Chambers (
http://www.diglloyd.com ) and Erwin Puts.
Best regards
Erik
SLR gear recently updated their ZA 24-70 test to include FF results, so I thought I'd post the comparison graphs, since there's been a lot of talk in the past months about comparing the two. Both seem like great lenses, with different strengths/weaknesses. The Nikon was shot on the D3, and the Sony on A900, and I'm not sure if the pixel count skews results. Enjoy.
ZA 24-70
Nikkor
