CCD filters

[Chad Wagoner]

I am looking to possibly add a filter wheel to my St-8300. Several questions arise.

1) Best filter? Astrodon v Baader v CS? What are the strengths and weaknesses?

2) Should I go with the 5 or 8 position wheel? My goal is to eventually do narrowband, but I plan to start with LRGB. I have semi-dark skies, but do suffer some light pollution up to 50 deg to the west. I like the idea of mounting the FW to the camera and not having to take it apart again to add more or to change out filters if I change my target.

3) Is there any advantage to waiting for prices to drop? I have not noticed much change in price on FW or fliters in the past.

As always, I greatly appreciate any and all advice. Clear skies!

-chad

[AllanR]

Chad,

FYI, my current setup is ST-8300M + FW8-8300 + Baader LRGB + optional IDAS LPS-P2, now to move on to your questions.

1) While I only have experience with the Baader filters, I'm happy with them, but this is my evaluation and how I ended up with the Baaders. I have not had any problems with reflections that some have reported. These may have been older filters or not installed correctly. You have to pay attention to the direction the filters are installed or reflections will be likely, and it can be difficult to see the difference or the arrow on the edge of the filter.
* In terms of transmission, Astrodon is best, followed by Baader (close) and CS (fairly far behind). (Astrodon Wins)
*Astrodon and CS each have gap (Astrodon's E-series is huge) between the red and green, the gap with the Baaders is fairly small. The gap helps with light pollution, but personally I would rather catch all the photons I can at a dark site and if I'm in a light polluted area I can add the LPS filter. (Baader Wins IMO)
* The Baader L filter leaks a bit in UV, but I don't really notice it. The other two sets don't have the leak. (Tie Astrodon/CS)
* Baader is much less expensive than the other two ($419 vs $595 vs $???). (Baader Wins)
* As far as I know CS does not make a set of 36mm round unmounted filters, so you would have to get a different filter wheel or at least a different carousel and either use 50mm filters (expensive) or 31mm mounted filters which may cause vignetting depending on your setups. (Tie Baader/Astrodon).

2) I completely agree with you here, and that's why I went with the 8-position, no complaints.

3) Probably not. I have never seen filter prices drop. Best you could probably do is wait for a double rewards sale at OPT or something like that.

Good luck with your setup,
Allan

[Chad Wagoner]

Well I went with the 8 position wheel, astrodon LRGB and Baader narrowband set. Tried to balance both cost and desire. Now just have to acquire some good images and figure out the processing. Thanks or the advice.

[Chad Wagoner]

Did you have to use the orings with the baaders? The narrow bands appeared to be about 1mm smaller than the astrodon lrgb so I used it with the baaders but not the ads. Any thoughts?

[AllanR]

I did use the o-rings for my baader lrgb filters, but I don't currently have any narrowband filters,so I don't know about those.

Allan

[Chad Wagoner]

The orientation for the baaders was a little confusing. The "v" on the side appears to have the narrow end pointing at the reflective coating which is placed on the scope side...correct?

Also did the orings peakout along he edges of the filter for you as well?