Started changing to SCT

I started changing the imaging optics over to a 9.25″ SCT today (from the 80mm dual refractors).

The basic mounting was easy during daylight, but I couldn’t set up any of the actual optical train because I can’t see anything far enough away to focus except at night with the moon or stars. So I waited until evening to start piecing optical bits together. I plan to set up with a 0.5 or 0.63x focal reducer for now, and an off-axis guider. Ideally I’d like to use the Van Slyke 3-port guider because of its flip-mirror functionality.
Evening testing was not good. The scope has fallen ‘way out of collimation during the year of disuse, couldn’t get various parts to work together, couldn’t find the right focus distance, etc. etc.

Back to basics, and I’ll work through the steps one at a time. Each of these steps will likely be at least one evening. Basic plan:

Set up visually, no focal reducer, no camera, nothing, and get the collimation perfect.
Start with a rough collimation in daylight using mirror reflection
Then do out of focus “donut” collimation on a star next clear night
Add focal reducer to the chain, get working visually. Focal reducer has to go outside the Crayford focuser to keep the focus distance in range. 80 to 110mm from reducer to point of focus is the target.
Add camera with off-axis guider inserted.
It might be necessary to try putting the focal reducer outside the off-axis guider to keep the focus distance in range.

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