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Star tune chick
I am making some modifications to my truss scope, and will need to spend some time tuning the stars back to as good as I can.
Out of the box the focal plane of the GSO scopes is really distant from the tube walls. With my camera / OAG / corrector I was still using 60ish mm of spacers to achieve focus. With an 88mm secondary, this meant that none of the 100% rays were getting to the camera. I am testing out increasing the distance from the secondary to the primary with some spacers, which let me move the camera back closer to the scope.
The end result is I should have a brighter image, because I'm not throwing away precious mirror real estate (If I have to lift it onto the saddle, I want to be using it) and there will be less weight hanging off the side of the scope, at a shorter distance.
So far its looking pretty good, now I just have to tune the tilt again. This one is an hour of each NB filter without playing around too much with the tilt.
Cheers.
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