Kidney Beaning Problem

[dazza1639]

I seem to be having a bit of an optical error occouring and I can't determine whether it's being caused by my focal reducer or wheteher its something wrong with my optics.

as you can see from the above image the Kidney bean shape seems to rotate around the centre of the image with the dark indentation towards the centre.

The image stack was taken with my NS8GPS an antares 6.3 SCT focal reducer 2" eyepiece adapter in which was inserted a canon 1000d DSLR with a 2" nosepiece and a skywatcher 2" LP filter screwed into the end.

I don't think I'm getting anything like this without the reducer (but I will have to check), thats why I think the cause must be the reducer. is this normal with reducers or is it because it was a cheaper version (£75 scope'n'skies).

Thanks

Darren

[Psychobilly]

The f6.3 reducer needs around 110mm between the back of the reducer and the chip... I use a 55mm SCT-T adaptor the other 55mm coming from the Camera and EOS T-ring...

[roundycat]

strange that the left centre one is so close to an otherwise perfect star.

Dennis