CCD Focusing

[Mybodycalc]

Hi guys, I'm going to buy a Colour CCD Camera for my Celestron 5"   Schmidt  Cassegrain, will I have problems focusing or do I need an adapter for it?

 

Thanks

[jacko61]

You'll need some sort of extension tube to fit between the camera's 'T' adapter and the telescope backplate.  According to celestron the optimum back focus for the C5 is 5 inches!...

What are the optimum back focus distances for Celestron SCTs? | Celestron

Graeme 

[jacko61]

Just to add to this, if you want round stars right to the edge of your image you would have to add the focal reducer/flattener which has a backfocus (i.e. the distance from the reducer lens to the CCD chip) of 105cm.

Graeme