Since de-forking it, I have replaced my Meade etx125's camera and eyepiece plastic back with an aluminum Wegat back.

 

Using that and the Celestron T-adapter SC and an adapter that connects everything to my a7, I had hoped to be able to use the etx125 as a telephoto lens.

 

But I am not able to bring anything to focus because the connecting tube is not the right length to bring images to focus onto the camera's sensor.

 

Does anyone know which connector is the correct one to use please?

 

The standard Meade fare is not likely to be any use since they were designed to attach to the plastic camera holder.

Also the haze that is so common in these old Summicrons very often does not clean up that well. Look for a good one

We are talking about prime focus here right? Not eyepiece projection. I had  my a7s attached to a meade etx-70at for a while. I was using a sony nex T-ring with the meade #64st T-adapter and worked just fine. I think you could have some better luck this way. If not then i quess you need spacers and you should ask more here www. telescopeadapters. com If i remember right the etx125 is about 1900mm which is very powerfull focal length for moon, sun eclipse shots but you have to know that these optics have severe chromatic aberration. But i quess you could post process this problem.Anyway good luck

Thank you very much Discordia.

Please excuse the delayed response; life and earning a living got in the way.

Still working on a solution to this matter. Will keep you posted.