What are decisive parts in a astrophotography dedicated laptop?

Yes. I actually know a lot about this as I am an astrophotographer—it is my primary hobby. This is the wrong forum for this though. For a relatively lightly traveled forum that I frequent go to
https://theskysearchers.com/

For a much more heavily traveled forum go to
https://www.cloudynights.com/

But in direct answer to your question, if you’re looking for a processing laptop, it kind of depends on what post processing software you’re looking for. But if you’re going the PC route, you really should have at LEAST an i5 but I’d go to an i7, and I recommend 16 gb of RAM or more. The video card is not important. It’s all about the RAM and processing speed. But in order of importance, I’d go RAM, then processing speed.

What is your experience? What equipment are you using? What software are you using? Can you upload a link to an image? (I changed my avatar to a narrowband image I acquired and processed last year)

Thanks a bunch, @Caravanfan.
I’ll write you in PM to show you a link to a picture of the Orion Nebula.
Don’t expect to be wowed though :-)

The Orion Nebula is where we all start.

@rebbel Send me the RAW or TIFF or whatever you use in a dropbox or something. I’ll fart with it a little.