HOTECH CT Collimator and Edge Hd 8

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James avatar
Hello,

I recently purchased the edge hd 8 and must have  bounced around while being shipped because it was out of collimation from the get go.  I decided to buy the HOTECH advanced ct laser collimator to help address the issue.  After reading a version of the instructions that came with it and watching the videos HOTECH put on YouTube, I started the collimation process.

after getting the co-alignment done, I removed the secondary mirror and noted that the crosshairs reflecting off the collimator mirror didn’t line up on the target.   The video said to make adjustments to the tilt plate, but the edge 8 doesn’t have one.  After doing more research, I realized there are several versions of instructions floating around. I downloaded version 9 and completed all the steps listed.  I am wondering if I do still have an issue in my optical train and am waiting for a clear night to test my collimation.   My question is this: if I do have an issue where, as HOTECH suggests, I would have to adjust a tilt plate, what is the workaround for the edge 8?


a second question I have is this: when collimating with the HOTECH, do you engage the mirror locks on the OTA?
THIBAUD Lucas avatar
Hello,

I can't help much because unfortunately I don't use any fancy tools to collimate the C8 edge.

I use first the donught technic to approximate the collimation, then I use tribathinov to get better and finish off with metaguide. since that my latest image has never been that sharp.

I don't have any knowledge in the Hotech collimator but adjusting tilt on camera must be done once the scope is properly aligned usually on RC and some astrograph you are aligning the optical train with the secondary i think that's what they mean. and C8 doesn't have a tilt adjustment plate compared to a CCA and other cassegrain astrograph.


Regarding the mirror lock unless you are using an additional Crayford for focus you juste want to clear mirror flop before collimation by finishing focus counterclockwise.
Dave Rust avatar
One Edge user’s experience: The “defocus donut” method is all I’ve ever needed on a Celestron (mine’s the 925). And I’ve not experienced mirror flop on the scope despite leaving them unlocked for the electronic focuser. Celestrons really are among the easiest reflectors to maintain.  I have a complete Howie Glatter collimation kit for my TPO, which benefits from it. But I’ve never had to use it on the Edge. In fact, I’m not sure the laser collimator would work on that design.
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