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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.
A very crisp and cold night. I added more luminance data and also collected some RGB for NGC 2841. There is now around 4 hours in L and an hour each in R, G and B. The subs are 114s at a gain of 139.
NGC 2841 is an unbarred spiral galaxy in the northern circumpolar constellation of Ursa Major. A 2001 Hubble Space Telescope survey of the galaxy's Cepheid variables determined its distance to be approximately 14.1 megaparsecs or 46 million light-years.
This is the prototype for the flocculent spiral galaxy, a type of spiral galaxy whose arms are patchy and discontinuous. The morphological class is SAa, indicating a spiral galaxy with no central bar and very tightly-wound arms. There is no grand design structure visible in the optical band, although some inner spiral arms can be seen in the near infrared.
The properties of NGC 2841 are similar to those of the Andromeda Galaxy. It is home to a large population of young blue stars, and a few H II regions. The luminosity of the galaxy is 2×1010 M☉ and it has a combined mass of 7×1010 M☉. Its disk of stars can be traced out to a radius of around 228 kly (70 kpc). This disk begins to warp at a radius of around 98 kly (30 kpc), suggesting the perturbing effect of in-falling matter from the surrounding medium.
The rotational behaviour of the galaxy suggests there is a massive nuclear bulge, with a low-ionization nuclear emission-line region at the core; a type of region that is characterized by spectral line emission from weakly ionized atoms. A prominent molecular ring is orbiting at a radius of 7–20 kly (2–6 kpc), which is providing a star-forming region of gas and dust. The nucleus appears decoupled and there is a counter-rotating element of stars and gas in the outer parts of the nucleus, suggesting a recent interaction with a smaller galaxy.
Equipment: Celestron 9.25 XLT at F10, Skywatcher EQ6 Pro GEM, ZWO 1600MM Pro, ZWO EFW with ZWO LRGB filters, QHY5IIC guide camera on Skywatcher 9 x 50 finderscope
Mosaic of the Large Magellanic Cloud One of two (known) companion/satellite galaxies of the Milkyway galaxy, located 160,000LY away and only visible from the southern hemisphere. Due to the angular size of the LMC, this image consists of 4 frames, each exposed in natural color at 500mm focal length through an 80mm refractor. The 4 frame are combined into one image to fit the whole satellite galaxy into the frame. The camera used was my astromodded and active cooled canon 40D. Exposure time was 2 hours and 42 minutes per frame for a total of 11.5 hours for the whole image.
I am new to astronomy, and recently purchased a Celestron Starsense Explorer LT 114AZ, and just for a start, I used the finderscope to locate exactly a random star, and I looked through the eyepiece and just saw a blurry white image. I was using a 25mm eyepiece lens, and then decided to put on the 2x Barlow lens with the 25mm lens, and nothing changed. Is this normal? What should I do to improve?
So I made this diagram to explain my ridiculous thinking which is probably wrong on many levels. I am aware they are looking for planets within stars that have suitable or imitatable conditions to our planet to support the notion that "life could exist on other worlds" .... I wonder, (and this may already be the case) ... are they factoring the evolutionary development time , in particular from single cell to multicellular organisms and the other regions in the universe that will also share a similar time point as sol/ our galaxy is from the centre of the universe. I just wonder if it is a thing where they explore within a specific range because of a justified thinking that other life will also evolve in a specific region of the universe... where is my thinking incorrect ? much appreciate any input on this... apologies for my stupid picture.