FITS and Colour Data

[ChrisWSM]

Hi there,

I'm a little confused, and hoping for some light to be shed on this matter. I'm very new to astro-photography, so I apologise for my ignorance, up-front.

I have an ASI178MC (one shot colour) camera.

If I use FITS (in FireCapture) as a capture file type, does that always contain the colour data? If so, at what point does the colour data enter the processing process? In other words...I have a bunch of FITS files and when I run them through DSS, the FITS viewer and output TIFF show B&W!

Kind regards

Chris

[Marky1973]

The colour should come out in processing. You can do a bit of this in DSS just to see how good your data is, but most people would recommend against using any changes in DSS when you export to your processing application. The quick fix DSS can be done as per this tutorial

https://markwalkerscreenwriting.wordpress.com/deep-sky-stacker-tutorial/

you probably still won't see a lot of colour until you fully process it, but it will give you an idea of the data you have captured. But it is not unusual for the standard output file from DSS to appear B&W.

Have a look on YouTube for processing tutorials for your processing software and that should help you tease the colour out!

[ChrisWSM]

17 hours ago, Marky1973 said:

The colour should come out in processing. You can do a bit of this in DSS just to see how good your data is, but most people would recommend against using any changes in DSS when you export to your processing application. The quick fix DSS can be done as per this tutorial

https://markwalkerscreenwriting.wordpress.com/deep-sky-stacker-tutorial/

you probably still won't see a lot of colour until you fully process it, but it will give you an idea of the data you have captured. But it is not unusual for the standard output file from DSS to appear B&W.

Have a look on YouTube for processing tutorials for your processing software and that should help you tease the colour out!

Thanks Marky

I was/am worried I'd wast a night's imaging, only to find the FITS are B&W! It's a huge learning curve, that sadly is much dependant upon the weather here!

I'm off to look at that link...is it your tutorial?

Regards

Chris

[Marky1973]

Hi Chris 

It's my take on other tutorials I have read. It's basic, but will help you get started. There is a ton of stuff on You Tube though, so plenty to get your teeth into while you wait for the clouds to disperse.

Although it feels like it sometimes, I don't think any nights you get out are completely wasted... I find I learn something each time... just not always what I was hoping to learn when I started setting up!?

[glowingturnip]

are you looking at your FITS files before they've been debayered ? (https://en.wikipedia.org/wiki/Demosaicing).

if you look closely at it and can see a very fine regular grid over the whole picture then it's not been debayered yet.  Any software package you use for processing will do the debayering for you, probably without you even knowing it

[ChrisWSM]

Sorry for the delay...

I was looking at them using Fits Liberator to examine the header. It reported Gray 8 bit images. I'm not sure how/why as there's no control over this, in capture software. So I'm confused. It's been rubbish weather here, overnight, for some time now. I'm going to get out there as soon as there's a chance, and run some tests.

I've decided to use FireCapture for planetary only, and use SGP for everything else. My test shots of the ivy (not a Messier object... Was seriously imaging my garden wall!) looked perfect using SGP, and DSS.

[Davey-T]

Why are you capturing FITS files, your camera should capture 14bit files, you can process in Autostakkert 2.

Dave

[ChrisWSM]

12 hours ago, Davey-T said:

Why are you capturing FITS files, your camera should capture 14bit files, you can process in Autostakkert 2.

Dave

Hi Dave

This is where I confirm my beginner status  

Only because all the tutorials I've read, use FITS, DSS etc. Until I find my way, I have to rely on the guides available. I've yet to come across one that uses AS. I'm really at a loss as to why these files were 8 bit, but reading further info, I wonder if the "Highspeed" setting was active. I'll check the settings file, when I'm home, to confirm this. 

What would you recommend, Dave. 

[happy-kat]

You use the autosave FITS file output from DSS and open that in what ever post processing application you use.

[ChrisWSM]

1 minute ago, happy-kat said:

You use the autosave FITS file output from DSS and open that in what ever post processing application you use.

Will this lift the 8bit gray, to 16bit RGB? My worry is what I put into DSS is 8bit gray. Sorry, but I'm not sure I understand your message. 

[happy-kat]

You were using the tiff file as output from DSS, I was commenting only on your output file used from DSS.

[Davey-T]

Are you trying to capture DSO,s ?

Normally I capture solar system objects using Firecapture, you can set it to capture 16bit SER files, and process them in AS2 to get a single stacked image.

Never tried imaging DSO,s this way.

Not familiar with your camera, I see it's got small pixels, is it intended for DSO's ?

Dave