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Any 3 inch Barlow lenses made?

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#1 25585

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Posted 06 October 2018 - 06:30 AM

I only know of the 3 inch Paracorr.



#2 junomike

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Posted 06 October 2018 - 06:57 AM

No market for such IMO as most 3" eyepieces are long F/L used for low magnification in observatory class OTA's.



#3 OleCuss

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Posted 06 October 2018 - 08:09 AM

If you actually want one, you'll probably want/need to contact Harry Siebert:  http://www.siebertop...80mm 4 eyepiece the relevant part is near the bottom of that page.  I'm betting they are a low-volume product and he makes them as they are ordered so I'd expect a bit of a wait.

 

He'll even make 4" if you need it.  He also makes some really long focal length eyepieces and such.



#4 TOMDEY

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Posted 06 October 2018 - 08:10 AM

That does indeed go against the philosophy of 3-inch provision for visual use... which is the intent to avail VERY long EFL eyepieces.

 

But... one could easily Make giant Barlow be fitting good negative achromat to a tube...  Tom




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