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Baader T-2 90° Prism Star Diagonal Body with Carl Zeiss Prism # T2-01B 2456095

5.0 (5 Reviews) Read Reviews Write Review
Brand Baader Planetarium
Part Number T2-01B
Availability available

Product Info

Manufacturer Description

PLEASE NOTE: The Baader T-2 90-deg Prism Diagonal (with Zeiss Prism) consists of a diagonal body with prism only. It is provided as a basic component, without any nosepiece or eyepiece holder. It incorporates standard T-2 threads at the input (female T thread on the telescope side) and output (male T thread on the eyepiece side) faces. This permits the diagonal to be used as a compatible component along with the other Baader Planetarium T-2 adapters and accessories.

Baader Planetarium has just expanded their innovation in star diagonals. Now, the mid-size, flexibility, and cost of the T-2 Prism Diagonal make this the ultimate diagonal for high power planetary viewing, or in systems where back-focus or space is limited and a full aperture 2" diagonal will not work or is not flexible enough. One of the key features of T-2 diagonals - be it prisms or mirrors - is the large free aperture and the flexibillity to directly adapt onto almost any telescope system, without the bottleneck of a 1.25" barrel size which may cause vignetting in long focal length 1.25" eyepieces or when working with a binoviewer on top of the diagonal. That is precisely why Baader offers the body of all their T-2 System diagonals without adapters.

The Baader Planetarium T-2 Prism Star Diagonal is easily the finest prism star diagonal available today. The right angle prism is produced by Zeiss and is the identical prism that Zeiss supplied for use with their exquisite APQ telescopes. The famous Baader Planetarium 7-Layer Multi-Coatings ensure the image is bright and contrast and the oversized prism provides an oversized full clear aperture of 34mm / 1.34".

Like all the Baader Planetarium products, the mechanical quality and finish are superb. The precision machined aluminum housing provides a stress-free mounting and precise location for the prism, unlike the typical weak plastic or crudely cast housings found on lesser diagonals. Extremely low scatter and high contrast images are the hallmark of this prism diagonal. The end result is a lifetime diagonal that matches or exceeds the brightness and image quality of the finest mirror star diagonals. Users of fine refractors over f/7 as well as SCT users have found that the Baader Planetarium T-2 Prism Star Diagonal provides the sharpest and highest contrast images they have seen from any star diagonal, mirror or prism.

Modular T-2 System Design: The design of the T-2 Prism Diagonal enables it to be configured to exactly suit your needs. The input and output T-2 threads integrate with the full range of Baader Astro T-2 System components and other T threaded adapters. The telescope side can hence be configured to fit in 2" or 1.25" focusers, as well as directly on telescopes with specific threads such as original M44 Zeiss threads, Vixen OTAs or Russian Maks. The eyepiece side can be used with Baader's quick change ring #6 in order to mount the Mark V binocular viewer instead of an eyepiece (in order to achieve the shortest possible backfocus distance between telescope and binocular viewer) or alternatively mount 1.25" (not 2") eyepiece holders. It is also the perfect diagonal for use with the Baader / Zeiss Giant Binoviewer (replaces the normal prism diagonal). Not just a visual accessory, this diagonal also integrates well into digital imaging applications. The effective optical path length of the base T-2 Prism Diagonal with Zeiss Prism is 41mm.

Weight = 5.3oz. (150g)

Baader part numbers: 2456095 and T2-01B

Reviews

5.0 (Based on 5 Reviews) 100% of reviewers recommended this product.
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    1. Guest

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      Review by James J.
      1529708835
      Jun 22, 2018

      5.0 Baader Zeiss spec prism diagonal

      Pros:

      Cons:

      Comments:

      I use this with 1.25" and 2" nosepieces and with Eyehold 2 at the eyepiece end. I've primarily used it with SCTs to date and a small refractor. I have had the Baader Prism-1 for the past year and it was fun to compare it with this Zeiss spec prism. As good as Prism-1 is, this showed itself immediately to be better in terms of contrast and fine detail. Splitting Izar with an older C5 was a memorable image when comparing it at the same time with other diagonals I had available (mostly dielectric mirrors). If I could give it more than 5 stars, I would. To me, it is well worth the price of admission, being the finest diagonal I have used in decades.

      Bottom Line: Would you recommend this item? Yes
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      This review was provided courtesy of AgenaAstro.com

    2. Guest

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      Review by Ray T.
      1501124059
      Jul 26, 2017

      5.0 Excellent Diagonal

      Pros:

      Cons:

      Comments:

      I now own and use two of these terrific diagonals. One of the best things about the T-2 design is being able to attach directly to accessories; I bought this second one specifically for use with a filter wheel. With the T-2 direct connection, I gained more than an inch of back focus (shorter light path) so everything comes to focus in my scope. The Zeiss spec version also has a slightly larger clear aperture so that 2" eyepieces with field stops up to 34mm can be used without vignetting... but if you intend to use a 35+mm eyepiece, you will need a 2" diagonal if you do not want it to vignette. Performance is first rate. I especially like this prism diagonal on close double stars with a magnitude difference where its reduction of light scatter often allows a clean split. This is a fine diagonal.

      Bottom Line: Would you recommend this item? Yes
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      This review was provided courtesy of AgenaAstro.com

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      Review by Luke V.
      1483387794
      Jan 2, 2017

      5.0 Exceptional

      Pros:

      Cons:

      Comments:

      The reviews and testimonials on CloudyNights have said it all - the Zeiss prisms are the best. Substantial and almost worrisome improvements visible over generic mass produced dielectric diagonals. Reduced scatter and increased contrast work together with your premium eyepieces and APO to pull into perception the subtle threshold details in Jovian belts and features. Observe with improved authoritative ease the unique colors of the Jovian moons as they transit Jupiter. Resolve with improved ease the delicate feather-like wisps branching from the EZ zone structure, white ovals are easier due to contrast effects with neighboring hues, features within GRS pop with vigor etc.,

      Bottom Line: Would you recommend this item? Yes
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      This review was provided courtesy of AgenaAstro.com

    4. Guest

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      Review by star lover of Arizona.
      1453680000
      Jan 24, 2016

      5.0 Great prism

      Pros:

      Lightweight,Quality Lenses,Accurate,Compact,Easy to Use,Strong Construction

      Cons:

      Comments:

      This diagonal is used with a bino viewer due to its sturdy construction and great optical quality. Highly recommended

      Bottom Line: Would you recommend this item? Yes
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      This review was provided courtesy of AgenaAstro.com

    5. Guest

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      Review by Dave of Des Allemands, LA.
      1435363200
      Jun 26, 2015

      5.0 Great diagonal

      Pros:

      Lightweight,Strong Construction,Quality Lenses,Compact

      Cons:

      Comments:

      I installed this diagonal on my LX200 12". I machined my own adapters from brass to install Denk binos. It works great. Very secure connections with no chance of accidentally coming off. I've only used it for one viewing session but mosquitos were too bad to concentrate on the view.
      There should be a clear label on the diagonal that it is Zeiss prism.

      Bottom Line: Would you recommend this item? Yes
      Was this review helpful? Yes / No

      This review was provided courtesy of AgenaAstro.com

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