ASI071MC Camera and Esprit 120

[Nath2099]

Hi guys, I have the above equipment that I had some time to play with over the weekend. I had an issue whereby I couldn't get the camera to focus at all. I tried with and without the diagonal, threw in a barlow, nothing. The camera was definitely working as it would blow out when you wave a light in front of the scope.

I noted this morning that the camera has a back focus of 17.5mm, and the scope 75mm. Dumb question, but he scope back focus means 0-75mm right? This means it should focus pretty much with the focuser most of the way in?

Anyway, thanks in advance for any clues you may be able to provide.

[cometcatcher]

Can you try it in the daytime pointed at a distant tree or building?

[ChrisV]

I got that camera with a WO GT80. Not the same, but I needed about 30-40mm extension to get it in focus

[Nath2099]

Cool, thanks guys, I'll grab an extension and give that a go. Can you tell me off hand if it's a 2" diameter I need?

[Camelopardalis]

You need to use the included flattener and then work out your back focus correctly. With the included adapter, the sensor needs to be a further 55mm back.

[Striker]

yeah put the flattener on and get the 75mm from flattener to sensor, then you should be around the 7 mark on the focuser.

page 8 in the manual.