After quite a bit of frustration, I am now delighted with the performance of the Hyperstar. Good grief though. Centering the corrector plate, ensuring the sec. mirror holder is not tilted with respect to the corrector, rotating the corrector to minimise zonal errors, minutely altering the sensor – Hyperstar distance, altering the tilt of the sensor slightly…… Need I go on.
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Supporting amateur astronomers since 1890