I must admit, this appeared to be a daunting task at first examination. I did a lot of reading and watched some videos. The more I read about how critical the backfocus spacing needs to be, the more I dreaded the idea of doing this. I spoke to Starizona and got advice from them.
The best advice I got was a blend of all the ideas I read. I knew that I would devise a method and I knew that I would have to go very slow, backing out if I did it wrong.
Here is what I did. I cut a plastic strip out of a yogurt container about an inch wide and 4 inches long. This will be your mask to determine which screws are where on the image. All it does is block light so you can see where it is at on the image.
Here are the steps I took…in order.
1. Point your telescope with tracking on to a bright star straight up and center it. For me, that star was Vega
2. Defocus the star to make a donut. Defocus as much as you can and still can see it, so you can very clearly see the donut and how off of center it is. Your goal is to adjust screws to center the circles.
3. Put the plastic strip you made coming out from the telescope center to the edge and right by a set of screws. When you expose your image you will see where that set of screws corresponds to on the donut by the line blocking out the donut from the strip.
Image identifying push and pull screws as well as rotate screws
4. Find the set of screws that is either 180 degrees opposite or directly in line with the thinnest part of the donut. These will be the first screws you will adjust. You will figure this out quickly.
5. Your first adjustment is no more than a quarter turn. You will loosen that push screw you located in step 4 and tighten the pull screw – expose and image. What happened to the donut? Did you go the right way? If so continue until centered, and if not, reverse that process and back out – check and continue to back out ¼ turn more and recheck. Do NOT go crazy turning all kinds of screws.
6. The Hyperstar arrives very close to collimation and less is more when it comes to adjustments. Going slowly and focusing on adjusting 1 set of screws and at most another round with a second set of screws if needed, you can and will get this centered, all within a ¼ turn of how it arrives, providing it arrives with a small gap like what you see in the photo. That gap allows you some play to adjust.
Hyperstar with gap shown - circled in red
7. Now go ahead and focus your stars and look for how round they are across the entire field of view. You should be very close to perfect. Just don't go crazy adjusting screws. Make sure all are tight at this point, but not overtight.
That’s it, but If you want to go the next level in adjustment, just put on a tri-bahtinov mask and do some more very fine adjustment moving the correct set of push and pull screws until all 3 lines intersect at one point – it’s up to you.
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