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Back Focus Distance Tips

Started by brucesdad13, 01/25/2015 09:49PM
Posted 01/25/2015 09:49PM | Edited 01/25/2015 09:50PM Opening Post
Me again... I'm reading up on imaging and all of the terminology and gear. I've sort of capitulated on my quest for a HyperStar alternative and am now wondering about back focus. My camera currently has a C-mount w/flange focal distance of 17.526mm (I think this is the universal standard for C-mount?). Starizona says HyperStar backfocus from mounting thread to focal plane is 39.8mm. Assuming I am able to find a used Hyperstar for my C8 and put the camera where the seconary mirror usually goes... what does the setup look like? Hyperstar (w/possible filter(s)) -> spacer -> C-mount? And then I focus by moving the primary mirror?

Confused as always... wink [image from Baader website attached]

Attached Image:

brucesdad13's attachment for post 59045

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