Hi Terry, haven't been reading the list for some time, but thought I reply anyhow. I'm a bit puzzled that when using a 512x512 instead of a 256x256 you get (really?) bad results when you get reasonable ones for the smaller one, even if it is contained in the larger one. With the concerns I had about (too strong) variations of the PSF over the FOV you still should get a reasonably reconstructed image in the small subpart that was used to derive it...
That raises one or two questions on how you are doing things. Does your PSF go to 'real' space, or are you doing everything in fourier space? If you just had two images (sharp and unsharp), FFT them, build the quotient and call that PSF, then apply that (Fourier) PSF to the unsharp image than indeed this will work perfectly - but only for exactly this image, and it even doesn't depend on wether you align it or not (the PSF can/will also contain image shift information). The other thing is, how did you extend the small PSF to the large FOV? By padding with zeros? If this is not done properly things can go bad, too (FFT is normally sorted in a wrapped order). One idea what to try would be take the 512 field, divide it into 4x4 fields of 128, derive PSFs in these subfields, average them and apply the average (propperly padded) to the large image and see what that does. (The idea is that if you have only two images to create the PSF it will contain a lot of noise information that gets smoothed out that way and make the PSF more general). Another one would be to FFT the PSF back to normal space, have a look at it and maybe run some filters on it (median to remove singular peaks etc.). The abovementioned averaging could also be done on those PSFs... Cheers, Pit -- You received this message because you are subscribed to the Google Groups "Hugin and other free panoramic software" group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/hugin-ptx
