Eta how do i pull the gasses out without blowing out

[ehgore1978]

Ive just stacked nearly 4 hours of Carina theres a lot of data there but the centre blows out bringing it out. This is a quick crude editing with the blown out one just done to show how much nebula I have. Ive shrunk these aswell so i can upload at 200kb its just a bit of a bummer theres more gas i could pull out of it

[Atmos]

It is all about masking and dynamic range compression. If you mask the bright areas and stretch the background it'll preserve the brighter areas.

If you're using photoshop you can make two versions, one very stretched and another processing just for the bright areas. Mixing the two of them will help you get the best of both worlds.

[JA]

What to do depends a little on whether your 4 hours of imaging are all at one exposure or are bracketed in exposure. If bracketed in exposure, then Photoshop (say CS6) can help using HDR type image processing. If it isn't bracketed then it is possible to do something similar by "creating" the bracketed exposures in camera raw and then using HDR Photoshop CS6. Perhaps look for some youtube tutorials on HDR imaging, possibly.....
https://www.youtube.com/watch?v=j7xiyPEWkrg

OR ....
It is also possible to do the sort of thing shown in the tutorial in a more "handraulic" way using layers in Photoshop and dodging in detail in selected areas (the over exposed areas) by adjusting transparency. The image layers can be created in camera raw with various degrees of under, normal and over exposure.

Best
JA