Thread: Weird flats
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Old 16-09-2017, 10:03 AM
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DiscoDuck (Paul)
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Join Date: Apr 2014
Location: Adelaide
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Just thought I'd update the thread with the results of my flocking - in case anyone else has similar issues in the future.

Simply flocking two surfaces seems to make a big difference (before and after shots attached). I applied some adhesive backed velvet material to the telescope end of the focuser and the ring at the entrance to the hole through the primary mirror.

A shot with my phone looking up the focuser to a flat box changed from the before to the after shot. Most of that light left round the edge is from the inside of the tube that goes up through the primary mirror, but it is very minor and would be hard to flock without dismantling the scope I think.

A test flat (single frame so apologies for the coarseness) is attached. Apart from the fact it's a smidge off centre (I need to tweak my focuser's collimation and/or my collimation ring) it's a lot better I think. (The shadow of the OAG is only 10% off the centre - so I might leave that where it is for now).

Thanks again for the advice.
Attached Thumbnails
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