SW ED80 Pro question

[Axeldude]

So I've got my ED80 Pro today, I'm super excited!

I put it on my HEQ5 mount to align my finderscope etc so I don't have to do it tonight, all is going well.

Took a few test pictures and I've seen that there's a slight black gradient on the top and I have no idea how to fix this..

Is this normal or is there something wrong with the scope? If I look through the camera itself I can't see such black part on top..

Attached is a picture I just took.

[Stephen]

How are you attaching the camera to the scope?

[Axeldude]

I got a 40mm tube extender with T2 thread and attach my DSLR to it, the other side is a regular 2" EP connection.

[Axeldude]

So I've screwed my TS UHC filter on it and it seems to be working right now.. I guess I've tightened the bolts that keep the tube in place a bit too much.