Unlike diffraction blur ,Gaussian blur "leaks" enough high frequency
information into the image that it can be boosted and reconstructed
(indeed, a gaussian is a very special extremum case that results in
max
blur for the least loss of high frequency detail)
Convolusalated Moose replies:
I'm not sure how this applies. If Gaussian blur isn't part of what the
lens
does, why do I need to know this?
--'Cause the blind non-determinate deconvolution with FM likely assumes
a Gaussion PSF--usually works quite well.
But wait! How about a little exercise? Just as theoretical, in a
way, but the processing is real.
<http://www.moosemystic.net/Gallery/tech/DiffractionContrast/diffracted_s
weep.htm>
That is just a wonderful illustration of why the images do improve!! I
hope Dr. Focus admires this as much as I do.
Using a increasing frequency line pair image is often a good way to
explore these things. Mathematicians might argue that diffraction is
similar to convoluting with a circular PSF and the high freq data is
increasingly obliterated, requiring much more processing with a perfect
deconvoluting PSF for diminishing returns and borderline useless. So
even though the maximal detail frequency is not changed,the contrast of
what remains is enhanced
and that is all that seems to matter up to a point. So Moose slays the
diffraction monster with vorpal sword and keyboard. O frabjous day!
Callooh! Callay!"
Galumphing home now, Mike
--
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