Really confused about which button to select at start

Questions and answers about processing in StarTools and how to accomplish certain tasks.
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BrendanC
Posts: 20
Joined: Sun May 17, 2020 12:23 pm

Really confused about which button to select at start

Post by BrendanC »

Hi,

So, for the past few months, on advice I've read here and elsewhere on the interwebs, when opening an image (FITS format, stacked in DSS), I've been selecting the 'Linear' button, because I have not, to my knowledge, been stretching the image at all (I'm using a modded EOS1000D shooting in RAW format).

However, on using Auto Dev with these images, this has been happening:
4.jpg
4.jpg (115.64 KiB) Viewed 520 times
Very green. Super-green even. And it just doesn't get any better no matter how I process it. I thought it was my fault but on processing other sample images for example from Jeremy Lodriguss, I got similar results.

However, I just read this thread entitled 'Green Overdose' and sounded like my problem: https://forum.startools.org/viewtopic.p ... 69a7bdb2be

On reloading the image and selecting 'Linear, from OSC/DSLR with Bayer matrix and not white balanced', then applying Auto Dev, I get this:
5.jpg
5.jpg (164.44 KiB) Viewed 520 times
Less green, and much better to work with, and even though it looks monochrome, the Color module sorts it out nicely.

Now, one of the reasons I'd been selecting Linear was that I thought DSS changed the white balance, as per this thread: viewtopic.php?f=10&t=652&start=10 - which would preclude selecting the DSLR option.

However, on going through DSS, I see this option:
1.jpg
1.jpg (74.06 KiB) Viewed 520 times
... which implies that DSS really does not apply any white balance processing.

So, just once and for all, can someone please confirm that, for acquisition via a DSLR, and then stacked in DSS, provided white balance processing is turned off in DSS, I should be selecting the ''Linear, from OSC/DSLR with Bayer matrix and not white balanced' option, not the 'Linear' option?

Also, as a supplementary bonus question, how does my white balance setting on my DSLR affect all this?

Sorry for such a long-winded post but I've been on the verge of forgetting about StarTools because I just couldn't get it to work. But if I could just confirm this aspect (plus one or two others I'm about to post about separately) it would really help me out.

Thanks, Brendan
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Re: Really confused about which button to select at start

Post by admin »

BrendanC wrote:Hi,

So, for the past few months, on advice I've read here and elsewhere on the interwebs, when opening an image (FITS format, stacked in DSS), I've been selecting the 'Linear' button, because I have not, to my knowledge, been stretching the image at all (I'm using a modded EOS1000D shooting in RAW format).

However, on using Auto Dev with these images, this has been happening:
4.jpg
Very green. Super-green even. And it just doesn't get any better no matter how I process it. I thought it was my fault but on processing other sample images for example from Jeremy Lodriguss, I got similar results.

However, I just read this thread entitled 'Green Overdose' and sounded like my problem: https://forum.startools.org/viewtopic.p ... 69a7bdb2be
Were my comments in that thread helpful at all? E.g. this is expected behavior. See also the quick-start tutorial, the AutoDev documentation and videos like these (getting a bit old, but should still be relevant) that explicitly shows and explains this behavior.
On reloading the image and selecting 'Linear, from OSC/DSLR with Bayer matrix and not white balanced', then applying Auto Dev, I get this:
5.jpg
Less green, and much better to work with, and even though it looks monochrome, the Color module sorts it out nicely.
It should do so in both cases.
Now, one of the reasons I'd been selecting Linear was that I thought DSS changed the white balance, as per this thread: viewtopic.php?f=10&t=652&start=10 - which would preclude selecting the DSLR option.
However, on going through DSS, I see this option:
1.jpg
... which implies that DSS really does not apply any white balance processing.

So, just once and for all, can someone please confirm that, for acquisition via a DSLR, and then stacked in DSS, provided white balance processing is turned off in DSS, I should be selecting the ''Linear, from OSC/DSLR with Bayer matrix and not white balanced' option, not the 'Linear' option?
With that option checked (which is a quite recent addition specifically for StarTools - thank you DSS devs!), you can indeed now choose "Linear, from OSC/DSLR with Bayer matrix and not white balanced".
For other recommended DSS-specifc settings (with screenshots), see here. This documentation also specifically confirms you can use "Linear, from OSC/DSLR with Bayer matrix and not white balanced" if those requirements are met.
Also, as a supplementary bonus question, how does my white balance setting on my DSLR affect all this?
It doesn't/shouldn't; the settings are (sometimes) recorded in the RAW file, but not applied to the RAW data.
Sorry for such a long-winded post but I've been on the verge of forgetting about StarTools because I just couldn't get it to work. But if I could just confirm this aspect (plus one or two others I'm about to post about separately) it would really help me out.
That would be a great shame! The best thing I can recommend at this point is to try a - preferably recent - tutorial, workflow or chart. Or to post a dataset you're having trouble with for us to process, so we can share the workflow.
You will/should find that all StarTools workflows generally follow the same steps in roughly the same sequence. See here for many links, tutorials and documentation that should get your started.

Hope this helps!
Ivo Jager
StarTools creator and astronomy enthusiast
happy-kat
Posts: 239
Joined: Sun Feb 01, 2015 11:31 am

Re: Really confused about which button to select at start

Post by happy-kat »

I see IVO has already given links for further info.
DSS the latest version 4.2.3 is the version for you to be using and then when you turn on 'No White Balance Processing' everything else will fall into place (plus don't align RGB in DSS). This did not work quite right in older DSS versions so please check you are using 4.2.3 + coupled with ideally 1.6 + of StarTools.
BrendanC
Posts: 20
Joined: Sun May 17, 2020 12:23 pm

Re: Really confused about which button to select at start

Post by BrendanC »

Thank you both. :)

It was quite a surprise to me when I realised I'd been selecting the wrong button all this time!

I think previous pages I'd seen must have been based on older versions of DSS. It's great that I understand this now.
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