FZ200 Diffraction Limit - Panasonic Tech Service

Started Aug 27, 2013 | Discussions thread
Stephen Barrett
Contributing MemberPosts: 570Gear list
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Re: Modelling Spatial Frequency (MTF) Response Effects
In reply to Detail Man, Sep 2, 2013

Detail Man wrote:

The MTF of diffraction through a circular aperture is not Gaussian. It's so-called "Chinese hat" function is nearly downwardly sloping linear - except when near it's right-most position on the X-axis.

Where it comes to the MTF of a Photosite Aperture, that is a "sinc" [ sin(x)/(x) ] function. The addition of an optical low-pass ("AA") filter represents a mathematical product of two "sinc" functions that form a zero-magnitude point at some sub-multiple of the spatial sampling frequency

My vote would be to compute in the spatial frequency (MFT) domain. The results are then directly in the "units" of interest (magnitude as a function of spatial frequency).

Thanks for the explanations, Detail Man. I will PM you to take you up on your kind offer to send an MTF spreadsheet.

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