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Too much light pollution, too close?
Hello everyone,
I've been playing around with capturing more data (very simple colour data) and keep coming up with one of 2 situations. Image is weak and not a lot of detail or nearly white. Telescope is constant, 90mm f5.5 refactor, 2" 10:1 focuser. Cameras are Canon 5D MKII, 450D and a Nikon D7200. I started out conservative ISO 800, 1 min subs. M45 came out ok. Then I tried M42 and was a bit disappointed, with 40 subs I still didn't get much more than the centre cluster and nebulousness. So I bumped up the ISO and all I managed to do was blow out the centre so badly I won't even show it. So I switched targets last night and tried C103, 10 3 min subs, ISO 3200. The frames were nearly white with over exposure.
So I started to think about what was happening and would like other opinions. I've attached some photos of my backyard with mount setup, one of the view to C103 and a JPEG of the image captured. Please note the street lights in close proximity. I don't need any light assistance when I go outside, its like early morning just before sunrise, all the time.
I'm thinking that all that light bouncing around in my yard and onto the house is simply overwhelming the camera sensor with long exposures, and introduces more noise than can be compensated for in short exposures, masking detail.
Thoughts?
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