Question about 130GTX with field flattener

Roland Christen

There is no way the scope will cause this problem, so it would do no good to send it in. You can send the field flattener and we can check it out, but I doubt very much that it can cause what you are seeing. 

These cameras are notorious for sensor tilt. If you go on the AP user group there are many people who have had the same issue and have successfully fixed it by using some new software that is now available for this specific issue. Go to,and also, and ask our users to help you.


-----Original Message-----
From: 王宇轩 <coolwangyx@...>
To: chris1011@...
Sent: Fri, Mar 11, 2022 6:27 am
Subject: Question about 130GTX with field flattener

Hi Roland,

I have been trying to image with the field flattener for my 130GTX with a 6200MM camera. I have adjusted for tilt and for spacing following instructions on your website, but the stars at the four corners are not symmetric. One corner elongation is particularly strong when slightly defocused (inside of focus), such that my autofocus cannot reliably make the stars round. It is possible to manually make the stars round, but they will have to be slightly defocused (outside of focus).

I wasn’t able to fix this issue by adjusting spacing and sensor tilt. I have already spent weeks on this. Could I send the FF and/or the scope in for an inspection?

Thanks in advance,


Roland Christen