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C8-n secondary Collimation

Guest twintin

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Guest twintin

Hi guys can anyone tell me if you need to undo the centre screw on the secondary before adjusting the other 3 screws. Being a mak man i'm new to all this collimation malarky!

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The middle screw is used to tighten up the secondary assembly once it's in place lined up. When a scope is delivered new you often find it's very tight and takes some effort to budge. When it's like this it's difficult to do anything with the other three screws. So the center screw needs to be only slightly loosened about an eighth of a turn so you can collimate with the other three.


Then you can just snick the center screw up finger tight enough to hold it all in place - but not overtight. Whatever you do don't undo it completely cos the secondary will drop out and hit the primary damaging both. This adjustment is best done with the tube horizontal so if it's accidentally loosened too much it only drops in the tube at the top.


A secondary is much cheaper to replace than a complete mirror set. :)

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