Star Mask for Colour module

Questions and answers about processing in StarTools and how to accomplish certain tasks.
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Startrek
Posts: 13
Joined: Mon Dec 30, 2019 3:49 am

Star Mask for Colour module

Post by Startrek »

I just finished processing my first OSC narrowband image of M16 in version 1.5 and reasonably happy with the final image, however a majority of the small stars ended up bleached out by the background nebulosity colour and the Fat stars were not white but with blotchy edges etc... ( I used Stars , after trying Fat stars )
I decided to process a colour version so ( as previously done in RGB ) I selected a Star mask ( fat stars ) to exclude the stars in the colour mode but found all the small stars were blended in with the colour which I dislike
So I then changed the star mask to Stars and adjusted the mask but this mask doesn’t form a neat circle around the stars like the Fat Stars option , its blotchy and irregular
Is there any way to mask all the small stars with neat circles around the stars so I can apply some colour to my Stars or is this out of the capabilities of Startools due to the limited number of pixels that make up the smaller stars
NB My previous star masks seems to work in RGB like a globular cluster but when stars are immersed in and around nebulosity like my M16 narrowband colour image they get immersed in the colour
I’m probably being picky but I thought I would ask
Appreciate any advice
Thanks
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admin
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Re: Star Mask for Colour module

Post by admin »

Hi,

Would you be able to show (a crop of) an example of what is happening?

Depending on the image and characteristics, you could try changing Filter Sensitivity and/or Exclude Color. If this doesn't help, the 1.7 alpha version also has an improved star mask generator (which now uses signal evolution Tracking to better discern stars from noise grain), which may help push the Filter Sensitivity without creating false positives.
Ivo Jager
StarTools creator and astronomy enthusiast
Startrek
Posts: 13
Joined: Mon Dec 30, 2019 3:49 am

Re: Star Mask for Colour module

Post by Startrek »

Ivo
Thanks for the suggestion
I processed M16 again and used a Star mask ( Stars) during colour and adjusted feature size and filter a bit
The mask improved by capturing the majority small stars and then I just tidied up the big stars with Lasso
Took some time but a much improved star field against the coloured nebulosity
Thanks again
Martin
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