05-05-2011, 10:40 PM
[quote name='youpii' timestamp='1304612990' post='8083']
Thanks.
Maybe you should also measure sharpness at the mid-center (basically at the rule of thirds) when there's a gap between center & border sharpness.
[/quote]
Then it makes more sense to switch to MTF curves, instead of bar charts.
However, Markus usually posts sample images (Klaus does that a lot less), and sometimes they do offer information regarding the sharpness situation across the frame.
Look at the barn/shed image, shot with f9. It shows good sharpness also towards the edges.
The metal rusty profile bar shot at f2.8, shows good sharpness in the center, ok sharpness kind of still at your rule of 3rds distance from the center, and really quite soft results towards the borders. So we can see that towards the 3rds areas already resolution is lower.
Thanks.
Maybe you should also measure sharpness at the mid-center (basically at the rule of thirds) when there's a gap between center & border sharpness.
[/quote]
Then it makes more sense to switch to MTF curves, instead of bar charts.
However, Markus usually posts sample images (Klaus does that a lot less), and sometimes they do offer information regarding the sharpness situation across the frame.
Look at the barn/shed image, shot with f9. It shows good sharpness also towards the edges.
The metal rusty profile bar shot at f2.8, shows good sharpness in the center, ok sharpness kind of still at your rule of 3rds distance from the center, and really quite soft results towards the borders. So we can see that towards the 3rds areas already resolution is lower.