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Message: <blockquote data-quote="henry link" data-source="post: 3252304" data-attributes="member: 6806">Thanks for going to the trouble, David. I know taking these is a pain in the rear.The angular magnification distortion in the ZenRay image is reversed from the AMD I photographed in the Swaro (horizontal stretching instead of horizontal compression). That only happens when there is a very large amount of pincushion, so much that the AMD is overcorrected. Some eyepieces, like TeleVue Naglers and Panoptics, have that kind of distortion. I don't see the same thing in the Vanguard photo so I doubt that added pincushion distortion from the camera lens is the cause, but it's a good idea to make sure that the circles are photographed within a distortion free area of the camera field. When you look at a circle at the field periphery through the ZenRay do you see a horizontally stretched oval like the one in the photo? Henry</blockquote>