Is my Whirlpool over exposed?

[StuartT]

I got about 3h on the Whirlpool last night, but I am wondering if my exposure time was too long (120s) as it's quite a bright object. 

How do you guys decide on the right exposure time?

 

Ok, I had a second run at this. Better, I think. Thanks for your advice!

 

Edited March 26, 2022 by StuartT

[ONIKKINEN]

What does a single sub look like?

Difficult to tell if you have just stretched it to this point or if it was like this in the subs. But i am going to guess that there is no way 120s on M51 would be overexposed. Its a bright object for a DSO, but its not really bright enough for you to accidentally saturate pixels with it.

[Padraic M]

I suspect over-stretching as well. What did you use to process it? Did you capture with the 2600MC? I know that sensor is very sensitive but I'd be surprised if it blows out at 120s. For comparison, I was on M51 last night as well, and this is 3.5 hrs in 60s  subs with a 533MC (unity gain 100, offset 21). I believe Bortle 8 skies respond better to shorter subs. It's noisy, but not saturated.

Processed in APP with a 10% stretch, and finished with just a levels nudge in Gimp.

[Elp]

Always do a few previews before running a plan, it wastes time but better than affecting all the subs. Looks like no detail is clipped so you can adjust the exposure or gamma to dial it down.

[StuartT]

Brilliant! Thanks everyone.

1 hour ago, ONIKKINEN said:

What does a single sub look like?

single subs actually look fine, so I guess I've just over stretched.

59 minutes ago, Padraic M said:

I suspect over-stretching as well. What did you use to process it? Did you capture with the 2600MC? I know that sensor is very sensitive but I'd be surprised if it blows out at 120s. For comparison, I was on M51 last night as well, and this is 3.5 hrs in 60s  subs with a 533MC (unity gain 100, offset 21). I believe Bortle 8 skies respond better to shorter subs. It's noisy, but not saturated.

Processed in APP with a 10% stretch, and finished with just a levels nudge in Gimp.

Yes, with the 2600MC. I pre-process in APP then finish off in PI and PS. My sky is not too bad (Bortle 5/6)

26 minutes ago, Elp said:

Always do a few previews before running a plan, it wastes time but better than affecting all the subs. Looks like no detail is clipped so you can adjust the exposure or gamma to dial it down.

good idea

[Padraic M]

That looks better!