Quote:
Originally Posted by multiweb
Ha! That's clever. Never thought about using a bathinov this way. I assume your field curvature across the sensor is nill then.
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The field curvature of the RH200 is near enough to nil. The critical focus zone at F3 is about 10 to 20 micron. That is why the orthogonality of the sensor is critical for stars good to the corners. This is why any flexure is a major problem that does not matter at F5 to F10. Having a 3.5 X 3.5 degree field adds to these constraints.
I already had the lateral camera position adjusted and as usual clouds spoiled the party.
Using a Bahtinov mask for sensor alignment gives a visual image of what is going on. The trick is to remember the image is inverted in the camera.
Bert