M101 - difficulty processing

Questions and answers about processing in StarTools and how to accomplish certain tasks.
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Re: M101 - difficulty processing

Post by admin »


Acquiring signal of low surface brightness objects is daunting at the best of times, but with the moon out that becomes really hard (the moon's light can be subtracted by Wipe, but the noise component of that signal cannot!). This is one of the reasons why most AP'ers wait for the moon to disappear.

As others said, (better?) calibration frames will help a lot here - there is some strong horizontal banding visible that prevents real celestial detail from being brought out.

The Wipe module can clean up some of the calibration issues, but it is always preferable you fix these things during acquisition/pre-processing, rather than in post. That will always yield much better results, while you won't learn much from the specific hacks/workarounds you have to employ for one particular flawed dataset. That time learning specific hacks, tweaks and workarounds is better spent trying to improve your acquisition (though I can show you if you really want!) and working on (and learning) things that you can use every time across all datasets.

Pretty cool though - you captured a lot of other faint fuzzies, even at 20s subs.
Ivo Jager
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Re: M101 - difficulty processing

Post by el_hop87 »

Thank you very much- yes I think I will definitely make better use / plan calibration frames going forward! - I worked out the reason why my flat frames were not correct (iso was the same as light/dark frames and therefore too high!).

I will definitely aim focusing pre processing/ acquisition techniques and prioritise this, but if there are any useful hacks to know I would be keen to learn, especially given that I have just started using StarTools.

Thank you very much again! - this is a great forum and support network.

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Re: M101 - difficulty processing

Post by Burly »

iso best value is 800 iso for your camera.
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