Internal DERF ina Schmidt Cassegrain

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sulcis2000
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Internal DERF ina Schmidt Cassegrain

Post by sulcis2000 » Wed Jul 01, 2015 9:49 pm

What do you think about an internal ERF installed inside a SCT ota in front of the secondary mirror?
Could it be a good idea?


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Re: Internal DERF ina Schmidt Cassegrain

Post by DSobserver » Wed Jul 01, 2015 10:15 pm

;)

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Re: Internal DERF ina Schmidt Cassegrain

Post by marktownley » Thu Jul 02, 2015 5:36 am

Who knows Ale, uncharted territory. However, you are an experienced modder, if you are happy to risk the scope trying it then why not ;)
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Re: Internal DERF ina Schmidt Cassegrain

Post by mdwmark » Thu Jul 02, 2015 7:57 am

If you where going to try this. You are going to need a really good ERF 1/10wave or better on transmission. You would be going through the ERF twice. I would tilt it so the reflection would not go straight back to the main mirror. You might want to cut a fan or two to pull the hot air out of the tube also.
Good luck if you try it.
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Re: Internal DERF ina Schmidt Cassegrain

Post by marktownley » Thu Jul 02, 2015 8:06 am

yes, reflections indeed. Maybe a circular polariser or 1/4 waveplate needed then too?
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