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The Coming Oly EM1+12-40mm f2.8 MFT
#31
Quote:What does this exactly mean? Can diffraction be cancelled by lens design? How is it possible?
 

No it can't (as far as I know of). I'll try to rephrase my statement:

Before the release of the 12-40/2.8 all Olympus mft standard zooms had a maximum aperture of f/5.6 (or f/6.3) at the long end, which is equivalent to ~f/11 on full frame. At this point diffraction effects already start to kick in. Look at the test results for the 14-42R, for example, and you will notice that stopping down actually reduces the resolution of the image.

In contrast, stopping down the 12-40/2.8 by one or two stops should yield a better lens performance (as usual when stopping down a lens), because you're not instantly diffraction-limited. 

So, in the end, I expect the 12-40/2.8 to be the best performing mft zoom (produced by Olympus) at 40mm f/5.6. 

 

I hope that was somehow more clear now...  :ph34r:
#32
Quote:No it can't (as far as I know of). I'll try to rephrase my statement:

Before the release of the 12-40/2.8 all Olympus mft standard zooms had a maximum aperture of f/5.6 (or f/6.3) at the long end, which is equivalent to ~f/11 on full frame. At this point diffraction effects already start to kick in. Look at the test results for the 14-42R, for example, and you will notice that stopping down actually reduces the resolution of the image.

In contrast, stopping down the 12-40/2.8 by one or two stops should yield a better lens performance (as usual when stopping down a lens), because you're not instantly diffraction-limited. 

So, in the end, I expect the 12-40/2.8 to be the best performing mft zoom (produced by Olympus) at 40mm f/5.6. 

 

I hope that was somehow more clear now...  :ph34r:
 

Yes, this is also what I understand it. I thought Olympus had some magic tricks to deal with optical diffraction :ph34r:
#33
Robin Wong published a comparison of E-M1 with E-M5: http://robinwong.blogspot.com/2013/10/ol...with.html. It is hard to judge E-M1 has 1-stop advance over the E-M5 in high ISO. The in-camera anti-diffraction feature (by some kind of smart sharpening approch) looks remarkable, but is useless for RAW shooters.

  


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