DSS Settings

General discussion about StarTools.
Post Reply
midnight_lightning

DSS Settings

Post by midnight_lightning »

Hi,

I have been searching the forum for information regarding the best settings to use in DSS prior to processing in Star Tools. I have found bits of information in various threads but no "Guide".

Perhaps there isn't one, or maybe I just didn't find it, but if there is a Guide to DSS Settings could anyone nudge me in the right direction?

In particular I am interested to know whether to set any calibration/white balance to on in DSS, and also what setting to use when opening an image in Star Tools - i.e. I am using a Nikon D750, I think the setting should be linear but is it bayered, white balanced?

Thanks

Mid
ecuador
Posts: 98
Joined: Sat Jan 24, 2015 10:23 pm

Re: DSS Settings

Post by ecuador »

The settings that are relevant to StarTools are the RGB Channels Background Calibration and Per Channel Background Calibration which should be both "No". Despite that, the autosave image will still be whitebalanced, so when opening with StarTools you choose the first button. Now, I've tried the second button as well (not whitebalanced), and at least in my tests I did not really see a problem that way, but those are the instructions.
midnight_lightning

Re: DSS Settings

Post by midnight_lightning »

Thanks for replying, I've spent literally weeks experimenting and still haven't found settings that work fully. For example:

Camera vs Auto White Balance - both off?
Hot Pixel detection (on the Darks tab and Cosmetic Tab) - is it ok to use these?
RAW/FTS Settings - which should I use?

Which Bayer Transformation method - Bilinear?

When you open a file in Star Tools it asks for a data type, I find this really confusing. I may be wrong about this but I use a Nikon DSLR so from my perspective the raw files are bayered straight from the camera. I'm seeing the "Bayer Transformation" in DSS as debayering the images. So which data type do I use in Star Tools - e.g.
Option 1 "....was not bayered...." - well my image came from a DSLR so it was bayered in camera - so presumably I cant use this option?
Option 2 "...... was bayered...." - well my image was bayered in the DSLR so presumably it should be this one - but only if I can get the image without WB?

OR - when it talks about "bayered" does it actually mean "debayered", in which case it would be the other way around(?)

Do I have to use the Autosave file or can I "Save Picture to file" - some people suggest there is a difference?

Sorry, lots of questions - surely someone must have a DSS workflow to use with ST :)
Last edited by midnight_lightning on Thu Nov 10, 2016 10:09 am, edited 1 time in total.
Guy
Posts: 158
Joined: Thu Feb 19, 2015 8:35 am

Re: DSS Settings

Post by Guy »

Hi,

I asked some questions about DSS a while back. See this topic about DSS Settings in StarTools
I think it answers most questions.

If you are interested in getting rid of the white balance, look at this post on Eliminating white balancing when using DSS

I hope this helps.

Guy
midnight_lightning

Re: DSS Settings

Post by midnight_lightning »

Hi Guy,

Thanks for the link, I had already seen this but still wasn't sure about some of the settings.

This is the bit I'm really struggling with:

"So which data type do I use in Star Tools - e.g.
Option 1 "....was not bayered...." - well my image came from a DSLR so it was bayered in camera - so presumably I cant use this option?
Option 2 "...... was bayered...." - well my image was bayered in the DSLR but if DSS debayers it, presumably it should be this option - but only if I can get the image without WB?

So I'm assuming using DSLR RAW (NEF) files, processed with minimum settings in DSS, I should be using Date Type option 2 "Linear, was Bayered, is not whitebalanced"?

OR - when it talks about "bayered" does it actually mean "debayered", in which case it would be the other way around(?)"


The dcraw idea makes sense so I'll also have a look at that.

Thanks

Mid
Guy
Posts: 158
Joined: Thu Feb 19, 2015 8:35 am

Re: DSS Settings

Post by Guy »

Hi

Initially it can be confusing I know.

- If it is a (stacked) RAW image - either monochrome or white-balanced colour - select 'Linear, was not Bayered or is white balanced'
- If it is a (stacked) RAW colour image that is not white balanced - select 'Linear, was Bayered, is not white balanced',

if you are using RAW files as input to DSS the output is white balanced - so choose option 1 'Linear, was not Bayered or is white balanced' (note or is white balanced)

Edit: Another way of putting it is: Only ever select Option 2 'Linear, was Bayered, is not white balanced' if you have a Linear (unstretched) colour image which has been produced with a camera that uses a Bayer filter (or other Color Filter Array) and which has not been white balanced.

If it is a colour camera using a Bayer matrix (or other CFA) the image was Bayered - hence the description.
It may (or may not) have been subsequently debayered - but that is a separate issue.

Guy
Last edited by Guy on Fri Nov 11, 2016 2:13 am, edited 1 time in total.
midnight_lightning

Re: DSS Settings

Post by midnight_lightning »

Hi Guy,

I think I'm almost there with it, all going well until you said...

If it is a colour camera using a Bayer matrix the image was Bayered - hence the description
.

So, my Nikon (D750 DSLR) is a "colour camera", and my understanding (perhaps flawed) it that it is therefore a "Bayered" camera - i.e. it will have a colour filter array over the sensor array.

Ah, I think it just twigged, I use Option 1 because the file is linear and white balanced. The fact that it is bayered doesn't matter because of the or.

I've spent so long trying to get this right in my mind that I'm starting to lose it :)

Thanks

Mid
User avatar
admin
Site Admin
Posts: 3367
Joined: Thu Dec 02, 2010 10:51 pm
Location: Melbourne
Contact:

Re: DSS Settings

Post by admin »

midnight_lightning wrote: I've spent so long trying to get this right in my mind that I'm starting to lose it :)
That makes two of us (and I'm the one who came up with the darn description!) :evil:
It's a hard thing to explain in just a single button caption.

I changed it slightly in 1.4.324+

Use the 1st option if you have linear data that was;
1. not bayered at all
OR
2. was bayered but is already white balanced (for example by DSS)

Use the 2nd option if you have linear data that was;
1. Bayered
AND
2. not white balanced

Option number 2 lets StarTools know it can assign the green channel higher weighting (a Bayer matrix has twic the number of green pixels vs red and blue) when it needs to evaluate the luminance component. You will get a small noise reduction/tracking bonus from this.

Hope this helps...
Ivo Jager
StarTools creator and astronomy enthusiast
midnight_lightning

Re: DSS Settings

Post by midnight_lightning »

Yes that makes it very clear thanks Ivo, just one question if I may.

Am I correct in understanding that DSS always does white-balancing (Autofile.fts) even though the options (Auto WB and Camera WB are turned off)?

Cheers

Mid
User avatar
admin
Site Admin
Posts: 3367
Joined: Thu Dec 02, 2010 10:51 pm
Location: Melbourne
Contact:

Re: DSS Settings

Post by admin »

[quote="midnight_lightning"
Am I correct in understanding that DSS always does white-balancing (Autofile.fts) even though the options (Auto WB and Camera WB are turned off)?
[/quote]

Up until now, that seems to have always been the case, yes, despite these settings.
Ivo Jager
StarTools creator and astronomy enthusiast
Post Reply