Sanity check - SC for live-stacking then PI post-processing

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Broz
Posts: 53
Joined: Wed Mar 03, 2021 2:12 pm

Sanity check - SC for live-stacking then PI post-processing

#1

Post by Broz »

I really like live-stacking and my family enjoys the experience too. However, I'm slowly learning PixInsight and enjoying post-processed astrophotography as well. I don't want to give up live-stacking, or I would just collect with NINA. So to hopefully enjoy the best of both worlds I wanted to check if I have the right idea for collection in SC using live-stacking, but saving the raw images for later post-processing. I realize that I could apply darks and flats collected in SC to the images collected for live-stacking, but the PI folks seem to think that it would be best to do all processing (image calibration) in a single program. I would also like to guide with PhD2, and would also like to dither. So is it reasonable to:
1) collect individual frames as required for darks, flats and flat-darks (I have an ASI294mc) as FITS.
2) live-stack on a target, saving the subs as raw files as FITS.

I am not clear on how dithering works now in the context of live stacking. The 4.0 documentation says that you can do it in still camera mode, but can it also be done during live stacking? If not, then I guess I need to separate out my collections as either live-stacking or for post-processing. Thanks,
John
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Re: Sanity check - SC for live-stacking then PI post-processing

#2

Post by admin »

Hi John,

yes, you are correct that you can save the RAW (unprocessed) subs while live stacking for later processing in PI or similar. It is definitely best to do all the processing in one place - so create and subtract your darks/flats in PI too when reprocessing.

Live stacking will happily dither for you - run PHD2, enable 'Server' mode and set SharpCap up to connect to PHD and dither in the Live stack options. SharpCap will drop the exposure to 2s while dithering and if you set the right option for the 'Save RAW frames' in live stacking then the frames captured while dithering will not get saved.

cheers,

Robin
Broz
Posts: 53
Joined: Wed Mar 03, 2021 2:12 pm

Re: Sanity check - SC for live-stacking then PI post-processing

#3

Post by Broz »

Perfect Robin. So I assume I would not subtract darks and flats in the livestack, just create the frames separately in capture for later use in PI along with the raw lights stored by livestack. Thanks,
John
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Re: Sanity check - SC for live-stacking then PI post-processing

#4

Post by admin »

Hi,

you can do dark/flat in live stack if you want - the raw frames that are saved are saved before the dark/flat correction, so will be fine for processing in PI either way..

cheers,

Robin
Broz
Posts: 53
Joined: Wed Mar 03, 2021 2:12 pm

Re: Sanity check - SC for live-stacking then PI post-processing

#5

Post by Broz »

Thanks Robin, that corrects my mistaken ideas on this.
John
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