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QCVC Processing

I use freeware Astrostack to resample/combine/align the images and used it's
deconvolution and unsharp mask. It's a great fairly easy to use program.

In Astrostack, I use the maximum width that will hold the number of samples I have, given by:

Width in pixels Max # of samples
192 455
256 256
320 163
384 113
448 83
512 64
576 50
640 40

If you notice my last pics up on Mike's site, I had around 80 samples, so I used 448 width. The December ones a had about 110 pics so I used 384 width. Below is a typical shot of my settings

I also usually use as large of a resampling that will still fit the planet on the right-hand result screen with "Full Image" checked, or one below that. Without the barlow, you could get pretty high, especially as your width gets larger. As you can tell, it's a balance, and you just have to play with the settings. I usually start just playing with the first 2 pictures in a set to get the setting I want without it taking a lot of time.

As far as choosing the best out of a bunch, I can only offer what I do:

I usually take a minimum of 5-7 sets of 99 in fairly rapid succession, sometimes playing with the settings (slightly) along the way. Stick with 320, as the 640 is only interpolated. When I'm done, I take those and run each set through Astrostack as is (usually at 384 width and 3x sampling). I chose the best 2 sets that are within a minute or 2 of each other. I reload them in Astrostack and just run through the "Nr. of input picture" arrows to cycle thorough the pictures. I make the pictures start at 01 rather than 00 to make the file number match the Astrostack number. I then just do a basic go-through of the pics and chose the pretty good ones. I'm not real picky, just get rid of the really bad ones. As a guide, I usually end up with between 70-100 out of 200, with fewer on bad seeing nights and more on good seeing nights. Once I have a directory full of the better samples, I rename and resequence the files for Astrostack (I have a bunch of perl scripts to do that). When I run these through, I usually get better results. When you Autoalign, align to one of your better pics, as that will bring our more of those details in the final product. Conversely, if you align to a pic with faults (interlacing or imperfections), you will bring those out more. I also usually take the result of Astrostack and run it through Photoshop (or any photo editing SW) and bump up the contrast and bump down the brightness. I also play with the color balance until I'm happy. Also, as the QC VC pixels aren't square, I have to rescale the width by 108% while keeping the height the same to end up with a correct perspective.

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