ZWO 290mm 135mm F2.8 spacing

edgar619

Hello...wasn’t sure where this question fit in topics so I started a new one. I have a 290mm and would like to take wide FOV nebula images with a Chinon 135mm F2.8 lens. I have the correct adapter to attach the M42x1 lens threads to my spacers. The back focus distance of the lens is 45.65mm +/-.02. What setup/ spacing distance from the lens to the sensor do your recommend ?

Thanks

Edgar

Support@ZWO

Hi there

ASI290mm has 12.5mm back focus, so there will be 45.65-12.5=33.15mm。

You will need a 33.15mm extender, one side is M42x1, other side is M42+0.75. But we don't have this adapter.

You could try contact with this company, they make customized adpaters.

http://www.preciseparts.com

edgar619

Thanks you ,