On 8/13/2009 2:55:26 PM, Jbryant61 wrote:
>
>>Convert the psf to an lsf
>>[line spread function](i.e. do
>>a vertical sum across the
>>psf), then do a basic fft (the
>>half size one) to get the MTF.
>>
>>Philip Oakley
>
>
>Hi,yes this is correct I
>mean't psf -> MTF.
>
>Thanks for getting me started.
>When you say do a vertical
>sum, do you mean a line scan
>thru' the centroid?
Nope, you sum down each column of the psf, so that
the peak gets 'sharper', which is what happens if
you image an edge. (actually a perfectly narrow
line - an impulse function)
so then you can do the fft of that edge/line, you
have the fft of the impulse, which is the
frequency spectrum, etc.
>
>BTW, I do feel guilty asking
>all these optics questions in
>a mathcad Forum. But to be
>honest, the amount of
>experience here is amazing and
>using Mathcad for this is
>extremely fun(and I prefer it
>to Matlab!)
So do I... MatLab has its place, but gets over
hyped. It is more of an efficient implementation
tool. And it is still stuck in the old
hack/compile/run/see mistake/hack cycle.
>
>Jason
Philip Oakley C.Eng
philipoakley@iee.org