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AstroViking
07-09-2022, 09:39 PM
Hey all,

I had hoped to add more data to this, but the clouds tonight put an end to that adventure. Maybe when the skies are clear I can add more data to this one.

This is 2 hours of data (120 x 60 second subs @ ISO400), but taken at a low elevation, so plenty of light pollution to look through. If I didn't have to go to work, I would have definitely taken a lot more images as the whale swam higher into the night sky.

Processed in Siril (lights, darks, flats and bias frames; background removal; 2 asinh stretches; no colour calibration or histogram stretch; green noise removal) and Affinity Photo.

Interestingly enough, NOT doing a histogram stretch in Siril gave better results - far less murky background noise, and an easier to work with galactic core.

Next time, I think I'll try for 2 minute subs at ISO 200.

Cheers,
V

Boring bit:
120 subs of 60 seconds, ISO 400
HEQ5-Pro + SW ES72ED@420mm + Nikon D7100 + Guiding

oska
08-09-2022, 06:48 PM
Hi Steve.
I would go the other way with ISO. More ISO less exp. I haven't tried DSLR yet but equating it to gain I'd go way more than double (800-1600+) and shorten the exp to compensate on your histogram. Even if I'm mistaken you (and I) will learn something :)

AstroViking
08-09-2022, 08:33 PM
Hi John,

As they say on TV, why not do both? :D Then I'll know one way or t'other what works.