ST processing quality is not that good for me

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maxthebuilder
Posts: 1
Joined: Thu Oct 06, 2022 8:12 am

ST processing quality is not that good for me

Post by maxthebuilder »

Hello,
I've been using ST occasionally for three years now.
Usually I process either with Photoshop or PixInsight but often re-process with ST just to see what comes out.
What I found is that ST is great for good broad band data sets.

For example I got very good results with targets like Andromeda, Triangulum and Orion. A+ here.

However, for targets not as bright, like dark nebulae (Dark Shark, etc.), ST doesn't play as nice.

And with dual narrow-band filters I never was able to get a good result with ST.

Maybe I'm doing something not right but anyway, just sharing my experience.

Thanks for a nice piece of software!
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admin
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Re: ST processing quality is not that good for me

Post by admin »

Hi,

StarTools should be able to produce substantially better (in terms of signal fidelity - matters of aesthetics are hard to argue obviously) results than either packages you mention. You should be seeing better (real/verifiable) detail amongst other things - no matter narrowband, visual spectrum, or partial spectrum data. If this is not the case, then that would be considered a bug of significant priority...

If you could provide a dataset and your StarTools workflow (also helpful would be the images from PS/PI), then we can better diagnose the problem you might be experiencing.

Thank you!
Ivo Jager
StarTools creator and astronomy enthusiast
hixx
Posts: 250
Joined: Mon Sep 02, 2019 3:36 pm

Re: ST processing quality is not that good for me

Post by hixx »

Hi Max,
How are You aquiring & process the Duoband datasets? I found these work nicely as Luminance files for (especially in light-polluted areas or for faint nebulosity within busy starfields.)

But I need to fulfill several requirements for good results:
1) The Duoband Stack (Luminance) has its own Calibration files (Darks, Flats)
2) I use a second stack shot through a clear filter of same thickness to avoid any difference in optical correction / distortion
3) Again, the color stack has its own Calibration files (Darks, Flats)
4) Both stacks are registered against the same reference frame
5) The Color stack needs much less expoure time but a far stronger WIPE. Usually a pretty strong overall WIPE on both stack does the job, though
6) In ST, I load the Duoband stack as Lum, and the Color stack into R, G & B channels.
7) Set Luminance, Color to: Luminance, RGB
8) You could also process both stacks independently first (no Bin & no Crop here) and then Combine those in LAYER in a second step
9) A yet more advanced way is to create LUM out of an LPS / CLS / UHC filter (broadband), the color stack with a clear filter for R.G, B channels and use the duoband in NBA channel. The latter 2 stacks wouldn't need as much integration time as noise is mostly perceived in LUM stack.
Depending on your site's bortle area, You might get more SNR using a broadband filter. Extreme narrowband filters may create better luminance SNR in cities though.

Clear skies
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