06-20-2016, 11:08 PM
The whole discussion is entering the theoretical realm really.
Here's a good background article that remains readable for most of us:
http://www.cambridgeincolour.com/tutoria...graphy.htm
At the bottom of the article is also a nice calculator - you should select the "advanced" option to make the most of it. Play around with the settings and be happy ever after.
In practical terms, using the standard 16mp sensor, the MTF50 peak performance is usually reached around f/2.8 (on MFT at 16mp). From there on dampening effects are limiting the resolution potential - that is on pixel level (using a gray target - which includes the blue spectrum, FWIW). As far as I'm concerned there can only be one physical effect responsible for this and it is diffraction - as a result of a number of SYSTEM factors.
Now does it matter that the (practical) peak is reach at f/2.8 (on MFT) ? Not really because the "plateau" spans till about f/8 before it collapses. At the end of the day this is the only relevant info for MFT users. Can we do something about diffraction? No, we can't.
I will close this thread now - it was about the Leica 100-400mm ... just in case somebody still remembers.
Feel free to open a new one though.
Here's a good background article that remains readable for most of us:
http://www.cambridgeincolour.com/tutoria...graphy.htm
At the bottom of the article is also a nice calculator - you should select the "advanced" option to make the most of it. Play around with the settings and be happy ever after.
In practical terms, using the standard 16mp sensor, the MTF50 peak performance is usually reached around f/2.8 (on MFT at 16mp). From there on dampening effects are limiting the resolution potential - that is on pixel level (using a gray target - which includes the blue spectrum, FWIW). As far as I'm concerned there can only be one physical effect responsible for this and it is diffraction - as a result of a number of SYSTEM factors.
Now does it matter that the (practical) peak is reach at f/2.8 (on MFT) ? Not really because the "plateau" spans till about f/8 before it collapses. At the end of the day this is the only relevant info for MFT users. Can we do something about diffraction? No, we can't.
I will close this thread now - it was about the Leica 100-400mm ... just in case somebody still remembers.
Feel free to open a new one though.