Thread: Which Filters
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Old 06-10-2011, 06:28 PM
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gregbradley
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Join Date: Feb 2006
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I have used Astronomik, Baader and a few sets of Astrodons. Who makes FLI research? Its proprietary knowledge of FLI. I suspect Custom Scientific do but I can't confirm or be certain of that.

The latest Astrodon Gen 11 are very very good, parfocal, equal exposure times or close to it. Baaders weren't absolute latest and had some reflections in green. They weren't parfocal ( a bit off) and they were definitely not equal exposure times. Astronomiks were good but they are thin (1mm) so you need a filter wheel that can handle them (FLI's latest per their site says they can handle any thickness filter, my CFW4/5 cannot). They have a later version out that Mike uses and his images speak for themselves.

FLI research are good and I thought everyone was happy with them but one guy recently posted reflections with his.

As far as Ha etc nm. I use 5nm and find them good. I have used them at F3.64 with an FSQ106ED and they work fine. 3nm I believe bring out more detail but require a lot more exposure time otherwise they could be noisy. I am interested at some point in a 3nm Ha as my setup with the CDK17 may require it and has lots of light coming in. 5nm sometimes isn't narrow enough when the moon is up and I get gradients.

So the filters I know work with Proline 16803:

Astrodon Gen 11
Astronomik latest and that's all I know. Baader's latest may be OK and FLI Research may be OK but best to post on FLI Yahoo Group for opinions as these filters are expensive as you know.

I personally like my Astrodon Gen 11. The Baaders weren't bad and are good with red response.

As you probably know filter selection with 16803 cameras is critical as they will show bad reflections easily and there are a million posts about this topic as a result.

Edge blackening with a black paint pen is recommended. Perhaps Astrodon are doing that now. They weren't when I bought mine.
There is a cheap Testors black paint pen available from amazon.com that is recommended by others for this purpose. I used a black texta and it works but is not 100% opaque.

Baaders and Astrodons are made differently. Astrodons are cut from a sheet, Baaders are cut beforehand then coated. Some say that makes a difference with Baader's being the better method. But as I say, my experience has been Astrodons are very very good.

Greg.

Last edited by gregbradley; 07-10-2011 at 08:07 PM.
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