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Baader Hyperion Universal Mark IV Zoom (1 Viewer)

Those following this thread might be interested in this ongoing Cloudy Nights thread on the Kowa 25-60x zoom.

http://www.cloudynights.com/topic/569030-kowa-te-11wz-the-plot-thickens/

Notice that the OP starts out thinking the FL range of the eyepiece is 18mm-7.5mm based on the Kowa magnification spec of 28x-66x in the "500mm" Lens/Scope. In post #24 he discovers a magnification discrepancy and recalculates the eyepiece FL range as 20.4mm-8.4mm, which translates to a FL for the 88/77 series scopes of 504mm.
 
I've now heard back from Kowa Outdoor on Facebook, (via my daughter's account), that the focal length of the 883/884 is (cue trumpets), 500mm.

So now we know.

Pretty much what we thought and confirming Henry's valiant experimental efforts.
 
I've now heard back from Kowa Outdoor on Facebook, (via my daughter's account), that the focal length of the 883/884 is (cue trumpets), 500mm.

So now we know.

Pretty much what we thought and confirming Henry's valiant experimental efforts.

What the...!? Are you trying to tell me that all you had to do was ask!?
 
Those following this thread might be interested in this ongoing Cloudy Nights thread on the Kowa 25-60x zoom.

http://www.cloudynights.com/topic/569030-kowa-te-11wz-the-plot-thickens/

Notice that the OP starts out thinking the FL range of the eyepiece is 18mm-7.5mm based on the Kowa magnification spec of 28x-66x in the "500mm" Lens/Scope. In post #24 he discovers a magnification discrepancy and recalculates the eyepiece FL range as 20.4mm-8.4mm, which translates to a FL for the 88/77 series scopes of 504mm.

Henry,

You were right and my guess of the induced higher focal length by a different focusing lens was wrong...
The CN post mention "dark coatings" of the zoom. Would this be the reason why you noticed more light on the Baader? Would this also explain the lower transmission was mentioned here at BF for Kowa 88?
 
David,

I think they mean dark reflections returning from the coatings (implying high transmission), which does not match the Kowa eyepiece I looked at yesterday. It's reflections were pretty bright especially from the edges of both the eye and field lenses.

However, as they say in politics these days, I think I may have to "walk back" my earlier opinion that the Kowa zoom has much lower transmission than the Baader. I was able to spend a little time yesterday comparing the two and this time I found the brightness difference to be modest. Also a took a few quick and dirty photos through the eyepieces of light transiting them from a white surface. Those also showed only a small difference in transmission. I'll let you know if I come up with an explanation for such different experiences with the same two eyepieces.

Henry
 
What the...!? Are you trying to tell me that all you had to do was ask!?

Apparently so. Kowa Outdoors on Facebook responded the next day and followed it up with a query on what eyepiece (my daughter), was planning to use on the scope.

Maybe we should all get on Facebook, though personally I don't want all my details mined by all and sundry.
 
No social media for me either. I'm already a bit unnerved by what marketers and therefore unknown others seem to know just from my internet browsing and use of email.
 
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