Posts Made By: Gene Carsia

September 21, 2014 08:56 PM Forum: Reflectors

ES Comet Hunter/mak-newt collimation problems

Posted By Gene Carsia

My ES David Levy Comet Hunter has never given decent views since purchased. After hours of collimation attempts w/ a 2" Hotech laser and a combo Cheshire/sight tube I threw in the towel and shipped it back to ES. Their customer service is great, but when I received it was still horrible- when tried on the moon it was never in focus. Maybe rough shipping, so I recollimated it and the laser is spot on, but a "focused" star looks like a small doughnut and moving the focuser one way looks like a horizontal line and the other side of focus is a vertical line-?astigmatism. Any ideas on what would cause this? Please help if you can.



September 23, 2014 05:32 AM Forum: Reflectors

ES Comet Hunter/mak-newt collimation problems

Posted By Gene Carsia

Problem solved- removed the primary and was surprised to see the head of a large screw was protruding about 1 cm and actually made a divot in the mirror back due to the pressure applied when turning the collimation knobs. Once screwed in flush like the other two screws no more astigmatism. These screws can only be accessed by removing the mirror, so I can't see how I could have caused this problem. Anyone who owns this scope should be aware since I've never seen these screws on any other primary assembly. Anyway all's well that ends well. Rolando,thanks so much for your help.

January 10, 2023 05:31 AM Forum: Mounts

Meade 90 ETX tube to Polaris GEM

Posted By Gene Carsia

I just purchased a dovetail plate from Scopestuff for my recently acquired ETX 125 OTA. The dovetail plate bolts onto the foot that is attached to the OTA with 2 included bolts. Then you can mount the OTA on any mount that accepts a Vixen style plate.