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Cheshire collimator question

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I recently purchased an Astro essentials Cheshire from FLO https://www.firstlightoptics.com/other-collimation-tools/astro-essentials-cheshire-collimating-eyepiece.html

and I notice that the aluminium 45 degree reflector piece within this rotates freely. So everytime I have to do a collimation, I need to check and see if the reflecting face is indeed facing the hole in the tube!

Is this normal or have I got a defective piece?

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It's broken and needs replacing. While you're getting it replaced I would advise upgrading to the Premium Stellalyra one which is 1.25" for almost the whole height of the cheshire so you can better match the bottom of the tube to the apparent secondary size and which has much better crosshairs. The thin wire used in the cheap ones has a tendency to stretch and deform if anything comes into contact with it. The angled face/peephole is probably more accurately positioned as well, even comparing examples where they're not loose and spinning around.

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I may be misunderstanding your point but the “eye” of the Cheshire should be pointed towards a light source and you do this by rotating it in the focuser. 

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