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 se谢谢楼上的提示找到资料了
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