strange data from narrowband

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Re: strange data from narrowband

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almcl wrote: Mon Jan 11, 2021 10:25 am I've tried ASTAP a couple of times and had great difficulty getting it to work with the Canon raw files, but have since tried with the .fit files generated by my (new) ASI 2600. While it seems happier with these, it is painfully slow. A stack that DSS would have dealt with in under 3 minutes ASTAP is still churning away with after 20 minutes.

Has anybody else had a similar experience? Or have I mis-configured something?
That's an interesting datapoint, thank you! Was this with the StarTools-recommended settings? (they're a bit new still)
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Re: strange data from narrowband

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I think so, although I may have left the Colour smooth box checked and it definitely did not like my Bayer pattern setting. Just running it through again with (hopefully) these points addressed, but it is still looking to be a 15 minute job.
Skywatcher 190MN, ASI 2600 or astro modded Canon 700d, guided by OAG, ASI120, PHD2
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Re: strange data from narrowband

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I mis-spoke above - it actually took 31 minutes to process 30 light frames.
Skywatcher 190MN, ASI 2600 or astro modded Canon 700d, guided by OAG, ASI120, PHD2
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Re: strange data from narrowband

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almcl wrote: Mon Jan 11, 2021 5:15 pm I mis-spoke above - it actually took 31 minutes to process 30 light frames.
Hmmm... I wonder where the discrepancy might lie in terms of algorithms being uses, and whether this discrepancy gets reduced as more cores are being utilised.

How, in your estimation, does the stack compare between DSS and ASTAP?
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Re: strange data from narrowband

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The ASTAP stack is less noisy and I think shows slightly better detail. Here is crop of the central area of a run of 30 lights and 30 flats from last week, side-by-side for comparison:. The DSS stack first:
DSS
DSS
DSS Stack.jpg (40.28 KiB) Viewed 116 times
---
ASTAP
ASTAP
ASTAP stack.jpg (33.59 KiB) Viewed 116 times
They may have been processed slightly differently in StarTools (of course) and I think the conversion to jpg may have mangled them slightly (not converted in StarTools) and I am still trying to sort out issues with the new OSC camera - Dark Flats are introducing artefacts, there's a massive amount of tilt which a new focuser is on order to correct and I am not sure of the optimum settings for gain, offset and temperature.

I do wonder if ASTAP is using multi-core threading? So accustomed to ST's high speed processing now that much other software seems very pedestrian!
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Re: strange data from narrowband

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I tried it Ivo , I’m impressed easy to use once settings configured which was only a few tweaks simplest stacker I have used , and you can also use astap to find asteroids and comets etc
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Re: strange data from narrowband

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Burly wrote: Wed Jan 20, 2021 8:01 pm I tried it Ivo , I’m impressed easy to use once settings configured which was only a few tweaks simplest stacker I have used , and you can also use astap to find asteroids and comets etc
Great to hear (also from @almcl)! It's another positive datapoint for the ASTAP / StarTools combo. :thumbsup:
Ivo Jager
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