Help with how to prevent star bloating.

[GraemeH]

I'm hoping that some of the experts here can offer me some tips for photoshop processing of nebulae. I'm still very much at the beginner stage both for capture and processing and love reading the tips that are shared here to try to help everyone get better images. 

I'm quite pleased with what I've managed to get in my attached image of the Cocoon Nebula for the object itself, but I'd love to know how to get this effect without blowing out the stars around it. I'm vaguely aware of the concept of layer masking, but I'm not sure how to go about it. 

The image is a stack of 65 180" subs, calibrated with flats but no darks or bias. I did dither after every 5 subs though and advice seems to be that this negates the need for darks. Stacking was done in DSS using kappa-sigma clipping, then processing in PS CC 2018 using lots of small curves, levels and HSL adjustments. 

Thank you for looking. 

Graeme

[Davey-T]

Look up some tutorials on making a star layer so you remove the stars and process them and the nebula separately then stick them back together.

Dave

[SteveNickolls]

Good luck with PS. Here's the jpeg quickly dissected into star background and nebulosity then processed in StarTools using HEAL, LAYER, SHARP and LIFE modules.

Best Regards,
Steve

[martin_h]

 

[GraemeH]

28 minutes ago, martin_h said:

 

Thank you for this link - I'll work through this tonight.