Help with processing please

[originaltrilogy (Petr)]

Yes it is Hyperstar V3 on C9.25 and QHY8 original camera OSC.

I need to work out how to collimate properly.

Thank you Ivo you help is so very good and encourages me to keep imaging.

I will clean CCD and take flats next time.

Sculptor was 75 second exposure x 29 exposures = 36 minutes of data.

Was same night as Andromeda but much higher in sky of course.

Maybe I should go longer than 75 seconds? I do not know how to work out what 75s @ f2 is equivalent to @ f5 perhaps in refractor?

[originaltrilogy (Petr)]

I cleaned sensor and corrector plate and took new images last night of sculptor.

120 x 45 seconds. I will post files up here soon but looks much better.

I took flats but think I got it wrong.

[originaltrilogy (Petr)]

Here is my 2nd attempt!
Clean sensor this time and short 45s subs x 120 = 90 minutes data.
Moon was in the sky so light pollution is there.
Has anyone done sculptor with 45s subs on a refractor? I would like to compare to Hyperstar.

TIFF file.
https://www.dropbox.com/s/odpqpy29p2...45s-noflat.tif

FIT file.
https://www.dropbox.com/s/32rhrpjmfj...45s-noflat.fit

I would love if people would process these their own ways and post results!

[originaltrilogy (Petr)]

Is Nebulosity best to stack in, or should I try something else?