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Although this image is not of a planet, it is of a planetary satellite and I can't find anywhere more appropriate to post it.
Last summer I imaged (the locations of) some satellites of Jupiter and Saturn but have only just got around to processing them. One target was Albiorix, aka Saturn XXVI. Discovered in 2000, it is only 30km across, roughly half the diameter of the M25 motorway. At the time of observation it was magnitude V=21.5.
62 1-minute subs taken with an unfiltered SX814 on a 0.4m Dilworth were stacked on the mean motion of the satellite and the result compared with the MPC ephemeris and the DSS2 images. The stars are trailed; the faintest one nearby is catalogued at g=20.68 in Gaia EDR3. Its trailed image is marked with the asterisk and red arrow. Despite the low signal to noise, Albiorix shows up untrailed in precisely the correct location; there are no stars of comparable brightness at that position in DSS2 and there were no asteroids thereabouts at that time according to the MPC, so I'm reasonably confident of the identification.
Shooting date: 10/16/2020; Shooting time 23:00 - 23:55; UT + 3h; Location: village #Dinskaya, #Krasnodar Territory; Equipment: Telescope Sky-Watcher 150 / 750PDS; Mount: Sky-Watcher Heq5 Pro SynScan; LB 3x #Televue Powermate; #ZWO ASI 120MC camera; Visible diameter 22.04 sec. arcs; Gloss -2.37; Azimuth 134.31 °; Height 42 °; The illumination of the planet by the Sun is 97.7%; Distance from Earth to Mars 63.5 million km; km; Roller 120 sec Crop video frames 8 bit, 380x380, 30% of 12,615, (69) FPS; Software: FireCapture; gain 36 (36%), exposure 7,000ms, Brightness (offset) = 9, Histogram = 60%; PIPP; AS3; RS6; PS CC (2020)
The March edition of the Binocular Sky Newsletter is ready. As well as the usual overview of DSOs, variable and double stars, this month we have:
The "extra" star in Cygnus Goodbye Uranus Vesta at opposition Grazing occultation of 52 Geminorum A look at mass segregation in open clusters I hope this helps you to enjoy these spring nights with your binoculars or small telescopes.
To pick up your free copy, just head over to http://binocularsky.com and click on the Newsletter tab, where you can subscribe (also free, of course) to have it emailed each month, and get archived copies.
After many hours of fiddling round with Registax wavelet settings to process my own solar system images, I've always been curious as to how it actually works. In doing so I've put together my own image sharpening program which does something similar to Registax wavelets. For comparison, I've also added some general purpose deconvolution techniques which you'll probably be familiar with from other image processing software (like Wiener inverse filtering, Richardson-Lucy, etc). In choosing a point spread function to deconvolve with, one suprising result was that the typical stack outputs from Autostakkert work best with a Lorentz point spread function (with a minor modification). Deconvolving with a Gaussian point spread function doesn't really work. Deep-sky images seem to deconvolve best with a Moffat point spread function (which is to be expected - it's already well established that star profiles in long exposures are best approximated with a Moffat function).
On the whole, it's unlikely that you can sharpen solar system images much more in this program than you already can in Registax. You can see results from Registax wavelet (sharpening layers), inverse filtering (e.g. Wiener), and iterative deconvolution (e.g. Landweber) below. They all give very similar results. In all the techniques there's a similar trade-off between less noise but less detail vs more noise but more detail.
There are some quick start notes on the first page of the Readme here:
There are some examples of deconvolved images here (move mouse over image to see before/after):
Image credits are on the hyperlinks
The Windows download is here:
Example solar system tifs to experiment with are here:
And the project page is here (with Source code in the src folder)
If anyone finds it useful, do post here how it compares to other tools you use for solar system image sharpening.
The download and the source code are free, you can use it unrestricted for any purpose. The OpenCV and OpenCVCSharp components which my program use have licence information at the end of the Readme.pdf.