How to remove internal reflections

Frankenscope? Let's see it!***be advised that NOTHING in this forum has been safety tested and you are reading and using these posts at your own peril. blah, blah, blah... dont mess around with your eyesight when it comes to solar astronomy. Use appropriate filtration at all times...
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DJD
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How to remove internal reflections

Post by DJD » Sun Aug 13, 2017 1:49 pm

Dear All,
I am re-vamping my optical train in my PST mod. I use 2" UV/IR cut and 35nm Ha filters at various places in the train.
I suffer from some internal reflections and would like to try tilting these components to check if they are the source of the problem.
Stupid question - how do you tilt a mounted screw-in filter ?
Best wishes,
David
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Carbon60
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Re: How to remove internal reflections

Post by Carbon60 » Sun Aug 13, 2017 3:10 pm

Hi David,

Maybe it's possible to slacken off the inner retaining ring and wedge under one side of the glass to get a degree or two? Doing this for each filter, but in opposite directions might give you what you need.

Stu.
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bart1805
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Re: How to remove internal reflections

Post by bart1805 » Sun Aug 13, 2017 10:29 pm

Hi David,
Could the UV/IR cut be the source of the problem? At the moment I use a Baader D-erf and the B1200 Lunt blocking filter (with the ITF). When I tried it in combination with the UV/IR cut filter I had internal reflections. Without it I have not got them.
Bart.

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Merlin66
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Re: How to remove internal reflections

Post by Merlin66 » Mon Aug 14, 2017 2:42 pm

You don't need the UV/IR filter......
I have used a CP polarized filter to suppress reflections, sometimes works well.
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