Stacking of your images is the easy part, with many quality, free apps available.
But post-processing is where astrophotographers make their hard-won data really count.
StarTools lets you push your signal harder, with unrivalled fidelity.
The Color module is very powerful - offering capabilities surpassing most other software - yet it is simple to use.
The two aspects - colour and luminance - of your image are neatly separated thanks to StarTools' signal evolution Tracking engine.
You can convert everything you see to a format you find convenient. Give it a try!