Baader Planetarium

05/09/13, These eyepiece sets have not been available since February 2009. The Zeiss Abbe Barlows are no longer available as of today.

Zeiss Abbe II Eyepieces

A classic has been reborn for uncompromising planetary observers

The rumors are true. Carl Zeiss Jena is making a limited production of these legendary eyepieces exclusively for Baader Planetarium. Sold as a set of four, this collection consists of essential focal lengths with an improved lens design: 16mm, 10mm, 6mm and 4mm. No short cuts were taken with this production. Only the finest, ultra-expensive optical glass has been used throughout. The oculars afford a full 43 degrees apparent field of view that is free of distortion. Two additional internal stray light baffles yield ultra high contrast. Ultimate Zeiss high-efficiency multi-coatings provide perfect color correction and sharpness to the edge. Image brightness with these eyepieces is unsurpassed.

Roland Christen of Astro-Physics offers these comments after evaluating a pre-production set of the Zeiss Abbe II eyepieces:

" I have tried these oculars, and I can say for sure that they are sharp to the edge (assuming that the objective is free of coma, astigmatism and field curvature), and the image is very contrasty. The internals are clean and the coatings are first class. There is no ghosting of any kind, even with bright objects in the view, and no scatter. Planets are sharp with dark sky at the edge of the ball of the planet when using a good objective lens. Lateral color is well controlled and the field is flat and orthoscopic. The optical design is by Dr. Pudenz of Zeiss Jena, and the elements were ground, polished, coated and final assembled at Zeiss Jena".

The Zeiss Abbe II eyepiece design features four tiny razor sharp triangular cutouts (field marks) spaced at 90 degree intervals in the field stop of the eyepiece. These triangles act as a virtual crosshair for object centering and field size drift measurements, but of course, do not put an actual crosshair into the field. A star may be placed into one triangle and when the star gets to the opposite triangle, it is proof that the star went through the center of the field of view.

Concerns have been raised about the potential distraction of the cutouts when observing the moon, Sun, or other daytime scenes. They will not be noticeable for deep sky or planetary viewing. For these customers, we will provide eyepieces that have been modified with black paint covering the triangle cutouts, effectively removing them from view. However, Thomas Baader, President of Baader Planetarium strongly urges that customers carefully consider the long-term historical value of these optics before ordering them with the triangles eliminated, as the alteration cannot be undone. In an open letter to Astro-Physics customers dated July 24, 2008, he writes:

"We do not recommend that anyone prematurely have the Abbe II micrometric field marks eliminated . . .

Any owner of a set of ABBE II oculars who imagines that this feature may prove to be objectionable should take comfort in the fact that the four field marks can be easily (and permanently) removed simply by applying four tiny opaque droplets of flat black optical paint. Consequently, at this time we are recommending that customers accept delivery of the Abbe II eyepieces as they were designed and fabricated by Zeiss and simply try them. We will remove these four marks free of charge for any customer requesting this service.

In any event, these field marks are part of a unique design that is no doubt destined to be regarded as a collectible of historical significance. Every owner of these eyepieces should think long and hard about (permanently) removing them, thereby possibly detracting from the future market value of a cherished set of unique eyepieces."

Click here to read Thomas Baader's letter.

We have chosen to leave the decision up to you, the ultimate user. Astro-Physics is offering two different versions of the eyepieces as described below.  Please note each version is available with or without the Abbe Barlow.

Shipment of the modified eyepiece sets will be delayed approximately 4 weeks. Please note that cancellation of the modified eyepiece sets after the units have been modified will result in forfeiture of your entire deposit. Although the modified eyepieces may be returned for warranty repair or exchange, a full refund is not available. If you choose to return the modified eyepieces because you are no longer interested, a 50% restocking fee will be applied.

For all customers who purchase an unaltered Abbe II set from us, Astro-Physics will offer a one-time triangle elimination service (blacken the triangle cutout areas), free of charge, three months after the eyepieces have been sold. Restrictions apply to this service, which include:

  • Set(s) must have been purchased from Astro-Physics
  • Customer must be original purchaser of set(s)
  • Entire set must be modified at one time (no partial sets)
  • All sets to be altered must arrive in time for the process. You must call or email for a return authorization no later than January 30, 2009. Complete eyepiece sets must be received between February 2 and February 6, 2009. The eyepieces will be altered and ready for shipment back within a couple of weeks. This process will only be done once with all sets in one batch. We will not perform this service again at no charge. There will be no exceptions to this policy.
  • The customer is responsible for all shipping charges to Astro-Physics as well as all shipping charges for the return shipment.

When matched with a Carl Zeiss 2x Abbe Barlow lens (optional), eyepiece focal lengths are halved without any redundancy or compromise of sharpness and resolution.

For the ultimate viewing experience, use two sets of these marvelous eyepieces with the Baader Mark V Binocular Viewer! The incredible contrast and sharpness of these oculars combined with the comfort and virtual three dimensional effect of using both eyes will give views of planetary and lunar features that will seem to "pop right out" where you could simply reach out and touch them!

Walnut storage case is a free gift with purchase while supplies last. Each case provides storage for two sets of eyepieces (one set horizontal and the other vertical) and a Carl Zeiss 2x Abbe Barlow. Only one case will be allowed per person. Quantities are limited and will be confirmed upon receipt of shipment. Recipients will be notified when final payment for eyepieces is requested.

Match them with a Carl Zeiss 2x Abbe Barlow...

Using the Zeiss Abbe II eyepieces with a Carl Zeiss 2x Abbe Barlow lens doubles the effective focal length of the telescope, or conversely, halves the focal length of the eyepieces to 8mm, 5mm, 3mm, and 2mm without any redundancy or compromise of sharpness and resolution.

We would not recommend using the Zeiss Abbe Barlow with the Mark V Binoviewer.   If used on the eyepiece side, a Barlow magnifies inherent defects in the binoviewer’s prism.   The Zeiss Abbe Barlow also has too short a focal length to be used effectively in front of the binoviewer, even though it could be attached using the T-threads.   For binoviewer use, Roland recommends the BARADV in front of, and no Barlow behind the binoviewer if a Barlow is desired.

This barlow features the Baader ClickLock eyepiece clamping system that grips your eyepiece firmly using a 3-point contact that accurately centers each eyepiece. The ClickLock clamp is attached to the Barlow's body using standard T2 threads. The use of T2 threads greatly enhances the versatility of this Barlow in two important ways: It allows direct connection to a camera using a standard T-ring adapter, and it allows the addition of T2 extensions to effectively increase the magnification factor up to 3X, assuming that your telescope has sufficient in-travel to achieve focus. The effective change will vary somewhat with the eyepiece design you are using. We offer the following three T2 extensions:

  • 15 mm T2 extension (BP25A)
  • 40 mm T2 extension (BP25B)
  • 7.5 mm T2 extension (BP25C)
Approximate Effects of Extensions on Magnification Factor
T2 Extension Part #
Extension Length
Magnification Factor
2 X
7.5 mm
2.1 X
15 mm
2.2 X
40 mm
2.6 X
80 mm
3.3 X
120 mm
3.9 X


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This page was last modified: March 11, 2019

Astro-Physics, Inc.
11250 Forest Hills Road, Machesney Park, IL  61115, U.S.A.
Phone: 815-282-1513   Fax: 815-282-9847