DS Mod 50mm Lunt and 20mm PST Internal Etalons?

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AndiesHandyHandies
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DS Mod 50mm Lunt and 20mm PST Internal Etalons?

Post by AndiesHandyHandies »

Hi

I have a 100mm F5 telescope and an internal 50mm Lunt DS Etalon mod would give me a full Sun image, as a PST, DO/DE = 2. For Proms. 50(.8)mm lenses + and - 250mm fl. 50mm x F5 = 250mm.

And then have the option to DS a PST Etalon after it for Chromosphere details, with a sweet spot of course. 25mm lenses, stopped to 20mm, + and - 100mm fl. 20mm x F5 = 100mm. Need 2x Barlow after to give 200mm back focus for my PST Mod set up to be used as is.

Edited fl's to be F5 thanks to Mark.

Cheers. Andrew.
Last edited by AndiesHandyHandies on Thu Oct 28, 2021 8:10 am, edited 1 time in total.


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marktownley
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Re: DS Mod 50mm Lunt and 20mm PST Internal Etalons?

Post by marktownley »

Hi Andrew,

Yes, in theory. You will need a negative 50mm f5 lens to produce a collimated beam prior to the etalon, and then a 50mm f5 refocusing lens after the etalon.

Mark.


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