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Old 29-04-2012, 10:06 AM
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madbadgalaxyman (Robert)
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Join Date: Mar 2011
Location: Brisbane
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Alexander wrote:
Fact remains that my modified Hyperion and my humble TMB out performed the LVWs. I saw more stars in them. Isn't that what it's all about?

bad galaxy man writes:
Have you seen my post in this thread, comparing a 22mm LWW with a 20mm type II nagler (which is probably an unfair comparison (!!), as this Nagler is one of the very best designs in Nagler's "super premium" line of eyepieces).
The stars seen in the Nagler were noticeably brighter, and I had a fainter magnitude limit with the Nagler.

My impression of the LVW was that the actual light transmission of the LVW eyepiece was noticeably worse than the light transmission of the Nagler, leading to fainter images.

Could it be that the difference between the LVW and the other eyepieces you compared it with is something to do with the relative light transmission of the eyepieces?
(there are definite variations in the coatings, between different eyepieces......I don't think all of the antireflection coatings applied to lens surfaces are equal in effectiveness)

Sometimes, the images are brighter in a simpler eyepiece simply because it has fewer air-glass surfaces to reflect and scatter light!!

The use of a barlow is also a major factor; the fact is that , despite the bad reputation of barlows in some quarters, the narrower light cone of a barlow - at greater effective focal length - often also reduces the aberrations in the star images provided by an eyepiece.
(In my view, the idea of the bad effects of a barlow on views through an eyepiece has become something of an urban myth; an often repeated statement that has become
so-called "truth" due to constant repetition)

Last edited by madbadgalaxyman; 29-04-2012 at 10:19 AM. Reason: more
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