What happened here?

[peroni]

Finally got set up to image NGC7000 tonight. Guiding in place, taking 900s exposures using Atik 460ex and Ha filter. First two frames ok. Next two frames seem washed out. But by what?

These images have been loaded into PixInsight but not processed. No auto stretch applied.

Any ideas?

Surely cannot be any light pollution in an Ha filter!

[peroni]

I may have answered my own question here. Went outside to finish up and noticed the clouds had come out. grrr!

Pretty impressive to image through clouds 

[Eri]

damn clouds should be banned tbh, I've just come in from a 3 hour imaging session was hoping for a few more hours but looking like tomorrow night i'll be able to get another 3-5 hours so thats sometihng to hope for. 

It always amazes me how much can still be picked up through clouds 

[MilwaukeeLion]

I like the first one better, my advice is take more of those.  Still both are better than my current sky / cloud / snow occultation.

[D4N]

Cloud part way through an exposure can have some odd effects, though mine normally have a bunch of wiggles too when PHD2 loses the guide star.

/Dan

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