color in Star Tools

Questions and answers about problems with the software, modules or functionality.
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tomh
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Joined: Mon Oct 22, 2012 7:22 pm

color in Star Tools

Post by tomh »

Hi Guys.
I've been playing with the demo version of Startools and having a bit of a problem
with the color in Startools. I have processed my images from a DSII color camera, Darks
Flats, and bias frames along with debayering into a FIT file with out any further processing.
If I open that file with Nebulosity, the colors are there. If I open the same file with Startools,
I am unable to get the image to show any color. Surely it must be something that I don't
understand or I'm doing wrong. Any insight would be appreciated.

Regards
Tom

Crow Mtn Observatory (ROR) - Russellville, Ar.
Orion 8" Astrograph on Sirius Mount
EQASCOM control for the mount
Orion SSAG Mini guider
PHD Guiding Software
Meade DS II with Peltier cooling
SkyTools 3 PRO
Nebulosity 3
Celestron NexStar 6SE
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admin
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Re: color in Star Tools

Post by admin »

Hi Tom,

Haven't come across this problem before. Any chance you could share the problematic image with me?
By the way, it's never the user's fault; it's either 1. a bug, or 2. my fault for making the interface too hard to use...

Can you also tell me if the 'Filter' module is available right after opening the file? If not then StarTools (mistakenly) assumes the file is black and white (Filter only works with colour images).

What happens if you save the same file as a TIFF file and open that? Same thing?

Lastly, what happens if you bump up the saturation in the Color module to something ridiculous - does color start to show then?

Thanks!
Ivo Jager
StarTools creator and astronomy enthusiast
tomh
Posts: 4
Joined: Mon Oct 22, 2012 7:22 pm

Re: color in Star Tools

Post by tomh »

Hello Ivo

Here's the answer to your first question ... "Can you also tell me if the 'Filter' module is available right after opening the file? If not then StarTools (mistakenly) assumes the file is black and white (Filter only works with colour images)."

YES The filter is darkened out.

Now the second item ..."What happens if you save the same file as a TIFF file and open that? Same thing?"

No, the color image loads as it should.....

Now that said, I have not taken this process any further that my original inquiry... I'll
Play some more this evening (Yea, it's overcast outside....Perpetually it seems !!!!)

I'm not sure how to send you an image on this board !

Regards
Tom
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Re: color in Star Tools

Post by admin »

tomh wrote:Hello Ivo

YES The filter is darkened out.
Aha! The plot thickens... :) StarTools, for some reason, loads the image as a black-and-white image.
I'm not sure how to send you an image on this board !
The file will probably quite big... Would you have a Dropbox account by any chance? (signup is free!) Once you've uploaded it, you can share the link here.

StarTools currently doesn't like 'Extended' FITS files much, as there is no specified/standard way of dealing with their contents without user intervention. In the case of an 'Extended' FITS file, StarTools just loads the first extension that it can find that has image data and ignores the rest.
Is there an option to save FITS files as a FITS file that is of type 'simple'?

At least we have a workaround for now, which is exporting to TIFF...

Cheers,
Ivo Jager
StarTools creator and astronomy enthusiast
tomh
Posts: 4
Joined: Mon Oct 22, 2012 7:22 pm

Re: color in Star Tools

Post by tomh »

Good Morning Ivo
I Checked to see if I had any control of the FIT output file... I Don't
I am using Nebulosity 3 to capture and process my images. I'll download
DSS and see if there is any difference with regards to loading the image.

The Nebulosity file isn't that big 1.6 M... perhaps I could emai it to you...

Thanks

Regards
Tom
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Re: color in Star Tools

Post by admin »

PM sent with direct e-mail :)
Ivo Jager
StarTools creator and astronomy enthusiast
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admin
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Re: color in Star Tools

Post by admin »

Hi Tom,

Thanks so much for supplying the file - it really helps!
I had a quick look at the FITS header and it confirms my earlier hunch that it contains 'extended' image data chunks. You mention in your e-mail something about the image being saved as an "RGB FITS: ImagesPlus" compatible file, as opposed to a "Maxim" compatible file. I have a feeling the Maxim compatible file will load correctly into StarTools.

Long technical story;

I was able to find precious little about what the difference is between the two options in Nebulosity, but looking at the file you supplied, it appears that ImagePlus assumes that and RGB FITS file is a file with 3 seperate files embedded in them (one for red, green and blue). As far as I know that is historically incorrect behavior; the more compatible way of doing this would be to specify NAXIS =3(width, height, and color-channels-per-pixel) , with NAXIS3 = 3 (for 3 channels). The latter is what I assume MaximDL does.
NOST FITS standard specifies:
Arrays of more than one dimension shall consist of a sequence such
that the index along axis 1 varies most rapidly,that along axis 2 next
most rapidly, and those along subsequent axes progressively less
rapidly, with that along axis m, where m is the value of NAXIS,
varying least rapidly.

TL;DR - ImagePlus stores RGB FITS files in a weird an non-backwards compatible manner.
Ivo Jager
StarTools creator and astronomy enthusiast
tomh
Posts: 4
Joined: Mon Oct 22, 2012 7:22 pm

Re: color in Star Tools

Post by tomh »

Hello Ivo
Well, that was in interesting response to the problem. That sent me off to reading
a bit from the nebulosity manual. My conclusion after all of that is that the
"Flexible image Transport" file system isn't all that standard. I guess as with
all things, there are those folks that see things differently and will do contrary things
regardless. At any rate, I'll leave such matters to you software folks to sort
through.

Your system is just fine the way it is, as further processing in Photo shop for
instance requires a TIFF format (I think), so conversion to your program is
not a problem...

Your support for StarTools is GREAT. Keep up the good work.

Sincerely
Tom

Crow Mtn Observatory (ROR) - Russellville, Ar.
Orion 8" Astrograph on Sirius Mount
EQASCOM control for the mount
Orion SSAG Mini guider
PHD Guiding Software
Meade DS II with Peltier cooling
SkyTools 3 PRO
Nebulosity 3
Celestron NexStar 6SE
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