To use the Hyperion eyepieces as 2" eyepieces you do not generally remove the
1.25" nosepiece with its included lens grouping. Rather you just insert the
entire thing into the 2" holder, using care that the 1.25" barrel doesn't make
contact with the diagonal mirror (if using a diagonal).
As far as differences between the lenses in the main body of the various
eyepieces, though they produce similar focal lengths with the 1.25" nosepiece
removed, they do not have the same configuration inside the main body as they
are optimized for the various final focal lengths.
Final note about removing the 1.25" nosepiece - this is useful for the purpose
of inserting the available "fine tuning rings" and changing the focal length
(higher) or for using the eyepiece at a lower focal length though the edge
performance suffers noticeably.
Author of "The NexStar User's Guide"
Author of "NexStar Observer List"
------ Original Message ------
Received: 11:19 AM JST, 01/26/2011
From: "larry" <taborekle@...
Subject: [Baader-Planetarium] New with question
> Hi all,
> Just got my 10mm(?) Hyperion. Haven't tried it yet as it's darn cold
> I was hoping to purchase several Hyperions to use as both 1.25 and 2 inch
eyepieces. In looking at the Baader chart for the Hyperions, it looks to me
like if you remove the 1.25 inch barrel from the Hyperions (all but the
largest), that the remaining 2 inch eyepieces ALL have about the same focal
length, which is about 21mm. Huh? How could that be? If all the differences
in the focal length properties are in the 1.25 inch barrel extension, then why
not just have different 1.25 barrels and a single lens.
> Perhaps I'm not reading the Baader chart correctly. I'm hoping someone on
this list could give some insight.
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