Ring effect

[Shibby]

Last night there were some rare clear (albeit hazy) skies, so I thought I'd try a little imaging using my new Skywatcher light pollution filter.

Trouble is, I get this strange, large ring effect appearing on all images. I'm still new to imaging so maybe it's obvious to some of you what causes this - but I've never noticed this before, is it due to the LP filter? If so, I certainly wont be using it again

Cheers,

Lewis

[Merlin66]

Looks too large to be reflections from the filter more probably vignetting within the telescope.

Flat field frames should take care of that.

Ken