Quote:
Originally Posted by RickS
it looks a bit "wormy" like a decon went wrong? Even with ordinary seeing I would have expected more detail.
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Quote:
Originally Posted by strongmanmike
Wavelets and decon can kill an image ... creating what I call psuedo-detail that looks kinda like turning all the detail shapes into point sources and it is often very noticable.
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Quote:
Originally Posted by gregbradley
... tend to agree I would have expected more detail. Perhaps the seeing was not too good as well.
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Guys I think you are right. Thanks for the frank and helpful insight!
I am also a bit disappointed with the sharpness that I'm achieving. The FWHM on a 10 second focus shot on a good night near the zenith is typically about 2.2 sec arc. I think collimation is ok. We like living where we live, and it's a good dark site. Can't have everything. So as you quite rightly point out, I've been trying to over-compensate by decon and wavelet sharpening. Doesn't work.
Here is a reprocess of the
monochrome stack only
The stacked FWHM was 4.7 pixels, or 2.6 sec arc. So guiding, tracking, and stacking can only have added 0.5 sec arc and aren't really the main culprits. After gentle decon, the FWHM was 3.5 pixels, or 1.9 sec arc. The non-linear stretch brought it back up to an apparent 3.8 pixels or 2.1 sec arc. Trying to stand back a bit, I think these numbers aren't shameful. Moving forward, I think I can try to pick the best nights, and go easy on the sharpening.
Accepting the limits of the seeing, short of selling the farm and moving, I think the strength of our set-up is the ability to do pretty long runs on very faint objects in narrowband, but I hope you will put up with us posting the occasional galaxy even if it isn't our forte. It's fun.
Best,
Mike