StarTools

Hi
Can you use a mask on DEVelop module?. The notes say i can
I'm trying not the stretch the stars, by using an inverse star mask, so i don't bloat my stars in M42
The mask seems to have no effect?
Thanks for your replies
Regards Dom

Hi, I think you should try autodev and define a region of interest over M42.
If your background is noisy then fiddle with the small detail slider.
The stars will remain better controlled in autodev.

Hi Dom,

What @happy-kat says!
(the Develop module was created to emulate the look of photographic film, which saturates stellar profiles quicker)

As a side note, if you're a power user and are 100% sure you need a mask, you can use a mask on any module - even if it doesn't support masking directly - by using the Layer module.
Once you're done in a module, launch the Layer module and click the Undo->Background or Undo->Foreground button. Now you can use a mask to modulate the image as it was before the module launch and after the module launch.

Hi
Thanks for your tips, the autodev was better, but didn't remove the halo.
In Autodev, ignore fine details help button actually says "it doesn't ignore stars", so my stars still blow out
Any other hints (beside the star stink module) to reduce these star halos ?
thanks again

I'm afraid these halos are an acquisition issue.
There are a few things that can cause this; from atmospheric conditions (bad transparency) too aberration (cheap) filter coatings to chromatic aberration to secondary reflections in the OTA.
They are not something you should normally endeavour to "fix" in post processing, however you may have some success with the Filter module with the Filter Mode in Reject mode, a star mask, and perhaps some Mask Fuzz applied (to blend in the filtered parts better with the unfiltered surroundings).

Hi Ivo
Thanks, that's exactly what I was looking for ! Star toolss does so much I'd forgotten about that function!!
PS Yes, i think it's some nasty reflection in the Zwo Camera that i can't get rid of on bright stars
Thanks Again