How to adapt a Star Analyser 100 to a 2" filter wheel?

Science Spectroscopy
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Hi all,

I am upgrading my observatory with a new camera, filter wheel, auto-guider, … My new filter wheel is a Player One Phoenix 7 x 2”, with one free position. It happens that I also own a Star Analyser 100, which I would like to install in the filter wheel. I wonder if anyone has made an adapter with a 3D printer for such device. Any help would be appreciated.

Best regards,
Damien

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Hi Damien,

It would be prudent to do some research on the idea, because filter wheels are usually close to the camera whereas the Star Analysers are required to be specific distances from the sensor for optimal performance. The specifications of the lens or telescope and the grating determine those distances.

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Hi Damien,

An option is to use the mounting kit from Paton Hawksley and a blank 2 inch cell, described on my web page here

Note though that the SA100 is signficantly thicker than the SA200 and there is often not enough clearence. Also with close coupled filter wheels the spacing is not enough to give a good spectrum. It is because of these two issues than I developed the SA200 for this application.

Cheers
Robin

1 Like
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Damien,

Robin’s answer to you was an important one. (He’s a designer of the Star Analyser.) The SA100 is too thick for most filter wheels. And most filter wheels put a SA100 too close to the sensor.

It’s likely you need a star analyzer 200. See this discussion: The Star Analyser 200 - RSpec / Real-time Spectroscopy

You can plug your specs into our calculator to determine how your setup will work: Grating To Sensor Calculator - RSpec / Real-time Spectroscopy. I’d be happy to work with you on that.

And, for a 2" to 1.25 adapter, see: Using a Star Analyser on a telescope that requires 2" filters - RSpec / Real-time Spectroscopy

If you have questions, you can contact me directly.

Tom Field, Author of RSpec

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Thank you Roy, Robin and Tom, you provided me with very useful information. I used your calculator Tom and found out I would need grating to sensor distance three time more than provided by the camera (17.5mm) + filter wheel (21/2) = 28 mm. I understand that the problem arises because of the size of the C14. Since this instrument is dedicated to variable stars, it would not be practical to momentarily add a spacer when I want to take some spectras. If I am correct a star analyzer 600 would do the trick, but no one makes them. But you nay still have a solution I have not thought of!?
Kind regards,
Damien