strange data from narrowband

Questions and answers about processing in StarTools and how to accomplish certain tasks.
User avatar
admin
Site Admin
Posts: 3382
Joined: Thu Dec 02, 2010 10:51 pm
Location: Melbourne
Contact:

Re: strange data from narrowband

Post by admin »

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)
Ivo Jager
StarTools creator and astronomy enthusiast
almcl
Posts: 265
Joined: Wed Jan 21, 2015 7:15 pm
Location: Shropshire. UK

Re: strange data from narrowband

Post by almcl »

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
almcl
Posts: 265
Joined: Wed Jan 21, 2015 7:15 pm
Location: Shropshire. UK

Re: strange data from narrowband

Post by almcl »

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
User avatar
admin
Site Admin
Posts: 3382
Joined: Thu Dec 02, 2010 10:51 pm
Location: Melbourne
Contact:

Re: strange data from narrowband

Post by admin »

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?
Ivo Jager
StarTools creator and astronomy enthusiast
almcl
Posts: 265
Joined: Wed Jan 21, 2015 7:15 pm
Location: Shropshire. UK

Re: strange data from narrowband

Post by almcl »

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 4142 times
---
ASTAP
ASTAP
ASTAP stack.jpg (33.59 KiB) Viewed 4142 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!
Skywatcher 190MN, ASI 2600 or astro modded Canon 700d, guided by OAG, ASI120, PHD2
Burly
Posts: 390
Joined: Mon Aug 31, 2015 7:06 am
Location: Northamptonshie uk

Re: strange data from narrowband

Post by Burly »

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
User avatar
admin
Site Admin
Posts: 3382
Joined: Thu Dec 02, 2010 10:51 pm
Location: Melbourne
Contact:

Re: strange data from narrowband

Post by admin »

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
StarTools creator and astronomy enthusiast
Post Reply