I was thinking about my quest for sharpness, and was considering trying to do 
some research into what the aperture "sweet spot" is for each lens, and was 
wondering if anyone had already made a chart of them.

Then I wondered how much it really matters.  I've heard "a couple of stops down 
from wide open",  "anywhere between f/8 and f/16", and a couple other rules of 
thumb.   I do know that on some lenses, particularly the FA50/1.4, that 
stopping it down a couple of stops from wide open, makes a huge difference.  
And I suspect that if you look on an MTF chart, you might be able to easily see 
the difference between f/4 and f/8,  but is there a practical noticeable 
difference?

There is also the question of sharpness at the critical focus distance, and 
overall sharpness.  That a lens might be sharper at f/4 than f/16 at the focal 
distance, but with a lot more depth of field, more of the photo will be sharper 
at f/16, than at f/64.

I'm primarily interested in answers based on personal, practical experience, 
rather than theory.  My hunch is that as long as I'm not too close to wide 
open, or pushing diffraction limits, optimizing aperture for sharpness is not 
the most productive place to spend my time and energy.  That I'm generally best 
optimizing the aperture for the picture, and not trying to optimize the 
aperture for MTF.

--
Larry Colen l...@red4est.com sent from i4est





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