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Mike,
Very useful thread. I personally like the ME results, though the
VC result is good as well. Curious about the original image.
Was there plenty of black space around the planet? I've found that
if you crop (say with ppmcentre or like tool) the image too tightly
then ringing around the limb is more likely. Also a PSF too large
can cause that as well. I think Bird is right about wavelets
discarding a lot of information. I think for purely cosmetic
reasons at the end of the image processing trail they are ok. The
amazing thing about ME is that if done properly it can actually
restore some original information!
Speaking of PSF, has anybody used the MaximDL ME deconvolution?
I've discovered that an exponential PSF can sometimes yield spectacular
results if chosen carefully (i.e. endless runs on the computer). When a
sweet spot is found the number of iterations is quite important as well.
I think the exponential PSF tends to correct for the diffraction profile of
our telescopes whereas the gaussian is better for correcting general
fuzziness due to seeing. In the real world we have both.
If one wants to get a good estimate at the PSF you can capture a mag 3
or so star (same config as your planetary stuff) careful not to saturate the
star image and of course careful with the focus. If you resample the
planet, resample the star as well. Then you have the closest thing to
the actual PSF, a good starting point anyway.
Thanks for sharing your results!
Glenn Jolly
Arizona, USA
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