Deep Sky Stacker settings

[Adam1234]

Hi all, I'm just about to stack some images of M51 that I took last night, but I never know what the best settings to use are. Specifically the RGB background calibration. 

Do you guys check use 'RGB channels background calibration' or 'Per channel background calibration? And do you check 'Align RGB channels in final image'?

What are the advantages/disadvantages of these options?

If it helps, I was using the Skywatcher Evostar ED80 DS-Pro and Canon DSLR with the Optolong L-Pro Light Pollution Broadband Filter.

Thanks

Adam

[geordie85]

I never worry about that as I align all 3 channels in Photoshop afterwards 

[Erling G-P]

Of those you mention, I can only find 'Align RGB channels in final image' (Haven't downloaded the latest version yet, so maybe the others are new features?). 

'Align RGB channels in final image' is not checked, which I believe is the standard or recommended setting - I haven't changed it myself.

[Adam1234]

23 minutes ago, geordie85 said:

I never worry about that as I align all 3 channels in Photoshop afterwards 

How do you do that? 

[Adam1234]

9 minutes ago, Erling G-P said:

Of those you mention, I can only find 'Align RGB channels in final image' (Haven't downloaded the latest version yet, so maybe the others are new features?). 

'Align RGB channels in final image' is not checked, which I believe is the standard or recommended setting - I haven't changed it myself.

Per channel background calibration and RGB background calibration options are in the Stacking parameters section. I have DSS version 4.2.3.

 

[Erling G-P]

6 minutes ago, Adam1234 said:

Per channel background calibration and RGB background calibration options are in the Stacking parameters section. I have DSS version 4.2.3.

 

Ah, I see - I'm on 4.2.2 and do have those options too - just hadn't noticed the text was 'active', as there's a tic box next to it, so assumed they were connected when browsing the parameters.  Mine is set to 'Per channel background calibration'.

[Adam1234]

Cool, I'll try the per channel background calibration. Might try the RGB background calibration and align channels as well and see what difference it makes.

Any idea what 'reduce worker threads priority' mean?  I think mine is checked by default but no idea what that does.

[8472]

I no longer stack with DSS, but when I did, I was advised to deselect all background calibration options, and check the "Align RGB Channels in final image" option only. 

This was the recommendation when using Startools.

[Erling G-P]

1 hour ago, Adam1234 said:

Cool, I'll try the per channel background calibration. Might try the RGB background calibration and align channels as well and see what difference it makes.

Any idea what 'reduce worker threads priority' mean?  I think mine is checked by default but no idea what that does.

I looked in the manual, but can find no mention of it.  A search found this in another thread:

" on the same page as 2x drizzle there is an option to reduce worker thread. this basicly lowers the memory priority to the program. it will meen it takes a little longer to do but its well worth the wait."

My guess is that it's mostly relevant if you're running other programs simultaneously, and don't want DSS to gobble up all the ressources.

[Adam1234]

46 minutes ago, 8472 said:

I no longer stack with DSS, but when I did, I was advised to deselect all background calibration options, and check the "Align RGB Channels in final image" option only. 

This was the recommendation when using Startools.

Any idea why it's best to deselect background calibration options?

[happy-kat]

If using StarTools then don't use any of the align channels you want the data as is. And if using StarTools there is a guide on that website on what DSS settings to use.

 

[8472]

16 hours ago, happy-kat said:

If using StarTools then don't use any of the align channels you want the data as is. And if using StarTools there is a guide on that website on what DSS settings to use.

 

Not entirely correct.

I thought this also was the recommendation (I am also a member of the ST forum) until I read this...

https://forum.startools.org/viewtopic.php?f=10&t=1448

I got much better colour balancing with DSS RGB channel alignment checked. Everything else unchecked.

YMMV

Edited March 29, 2020 by 8472

[happy-kat]

Are you using  DSS 4.2.3?

[Adam1234]

2 hours ago, 8472 said:

Not entirely correct.

I thought this also was the recommendation (I am also a member of the ST forum) until I read this...

https://forum.startools.org/viewtopic.php?f=10&t=1448

I got much better colour balancing with DSS RGB channel alignment checked. Everything else unchecked.

YMMV

That link was a great help! Going to process again and turn off background calibration, but keep RGB channel alignment checked (also might process with unchecked and look at the effect, if any)

[8472]

4 hours ago, happy-kat said:

Are you using  DSS 4.2.3?

If you me, no I use APP.

I have tried it though, including debugging an issue prior release.

Edited March 29, 2020 by 8472