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Baader T2-01c diagonal replacement

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#1 ewave



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Posted 09 May 2013 - 11:42 AM


Just wondering if there is a suitable replacement for this diagonal since Alpine has it backordered for quite some time. I am wondering if the more expensive Zeiss prism t2-01b which I guess has an additional 3mm backfocus will be usable? Also, how would something like the Zeiss prism diagonal compare to the Televue everbright 1.25" diagonal when using for just monocular viewing?

BTW, I have the Baader maxbrights binos since this January.


#2 johnnyha


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Posted 09 May 2013 - 02:18 PM

The Zeiss is the "deluxe" version of the diagonal, the one that used to be standard issue with the Mark V binoviewers. It would work well with the Maxbrights but of course it cost almost as much again as the Maxbrights. But it's a truly great prism diagonal, as good as it gets. The Zeiss will have a little extra in-focus compared to the TV Everbrite for mono viewing. The view will be similar although many feel the prism diagonal shows just slightly less scatter on bright objects. You lose the advantage of attaching the Maxbrights directly to the diagonal body with the TV diagonal however, and that's a big advantage as far as getting extra in-focus because you'll lose over an inch.

#3 etsleds



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Posted 09 May 2013 - 03:13 PM

Very nice diagonal, with the right threading for the Baader binos.

One trick you can play with these diagonals is to use the 2"/T2 reducing ring and fit a 2" eyepiece holder. With the 34mm clear aperture, you get 25% more FOV possible without the mass and focus length of a 2" diagonal - covers the 17mm Ethos and 22mm Nagler, just misses on the 21mm Ethos and 26mm Nagler.

Maybe not a big deal nor worth the $150 investment, until you have a scope like the FS60C with limited focus range or are trying to keep an already very back-weight scope like a Mewlon 180 balanced on a Quarterhitch mount :)

You don't really lose much on many cats, either, since they tend to have 32-39mm baffle tubes.

Anyway, I digress...

#4 ewave



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Posted 10 May 2013 - 11:17 AM

Thanks for the replies. I was wondering about the total path length of the TV vs the Zeiss prism diagonals. I assumed the TV is a bit longer since Baader had their Zeiss prism diagonal pathlength at approx ~ 42mm. But of course this assumes using certain adapters (i.e. the T2-14 nosepiece) completely flush against the end of the focuser to get it this short? Does anyone think the prism diagonals will incur any false color on bright objects?
Again thanks for your insights.

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