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Looks like we might get a couple of hours with stars in the sky tonight, it's been crappy weather all week, so I have it back on the bench.
Last run I again got concentric stars inside focus but non concentric outside focus. The secondary offset is 3mm but it should be 5mm. That offset is built into the spider however the 2 short legs, the ones away from the focuser, are 2mm different. I think one has been stretched somehow and I've had to shim the other one by 2mm to get the bolt centered in the horizontal plane.
Is this discrepancy in the offset going to cause me grief? I seem to be having a lot of trouble keeping the secondary centered and round in the sight tube and pointing at the primary center at the same time.
Also these red triangles are rubbish, even with a halogen lamp stuffed down the tube, refection 3 is almost impossible to see. I notice they sell white and yellow center marks so maybe one of those would be better? I should mention that to focus an eyepiece in this scope you need about 80mm worth of extension tubes in the focuser so the autocollminator is not being used at the eyepiece focus position.
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