Baader 2" BBHS® Diagonal Mirror – 60 Years Vantablack Edition

• Limited anniversary edition marking 60 years of Baader Planetarium
• Vantablack® 310 interior coating: reflectance below 2% – stray light inside the housing is suppressed even more effectively
• BBHS® silver coating: 98–99% reflectivity from just over 390 to 2000 nm – brilliant colours and high contrast
• Glass-ceramic mirror with 1/10 λ surface accuracy – no glass path, ideal for fast telescopes too
• Adjustable: mounted on an adjustable cradle – ideal for binocular telescopes too
• 2" ClickLock® eyepiece clamp and 2" nosepiece with safety kerf included
• Made in Germany, supplied in an anniversary edition beechwood case

Baader 2" BBHS® diagonal mirror – 60 Years Vantablack® Edition

To mark its 60th anniversary, Baader Planetarium has developed its proven, adjustable 2" BBHS® diagonal mirror into a limited special edition. The focus is not on cosmetic changes but on a technical improvement with a clear goal: suppressing reflections and stray light inside the housing even more consistently.

To achieve this, the interior of the CNC-machined aluminium housing is coated with Vantablack® 310, one of the blackest surfaces available. With a reflectance of less than 2%, it absorbs considerably more light than conventional matt black paints (typically 3–6%) – even far into the UV and infrared. Light striking the housing walls outside the actual light path is almost completely absorbed. Especially for contrast-critical observing, for example of planets or faint objects, subtle differences in brightness and colour are preserved as faithfully as possible.

BBHS® – more colour, more contrast

BBHS® stands for Broad Band Hard Silver: the glass-ceramic mirror with 1/10 λ surface accuracy carries a broadband silver layer protected against ageing and corrosion by a hard, sealed protective layer. It reflects 98–99% of light from just over 390 to 2000 nm – with no stray light and no loss even at varying viewing angles. The trained eye sees more colours, especially on planets at high magnification.

The aluminium housing ensures rapid temperature adaptation and a steady image.

No glass path – ideal for fast optics

Unlike a prism, the diagonal mirror has no glass path: light is reflected only at the surface and does not pass through glass. This means no additional colour errors even on very fast telescopes. Baader therefore recommends the BBHS® mirror for telescopes faster than about f/6 – but it is equally suitable for slower optics.

Adjustable – for binocular telescopes too

The mirror rests stress-free on an adjustable cradle with three-point alignment. It is collimated at the factory on the optical bench so that the image shows no noticeable shift when the diagonal is rotated by 180°. In normal use there is no need to change anything. The adjustment option is intended above all for building fully adjustable systems such as binocular telescopes.

Modular and securely clamped

• 2" ClickLock® eyepiece clamp: holds even heavy eyepieces securely with a 20° turn, with minimal tilt and automatically on-axis
• 2" nosepiece to 2"/SCT with safety kerf (grooves that prevent tilting and slipping out)
• Directly threadable: on the telescope side, the diagonal can be screwed to the focuser or accessories via M48, 2"/SCT or M55 for a short, tilt-free connection
• Tip: a 2" filter can be permanently threaded into the inside of the 2" nosepiece – leaving the filter thread on the telescope free

Made in Germany

The anniversary edition is made in Germany to the greatest possible extent: the turned and milled parts are produced on Baader's own CNC machines in Mammendorf, and the optics are polished and coated in Germany. Each diagonal is then assembled, collimated and tested in Mammendorf. It is supplied in a black-lacquered beechwood case made in Austria specially for the anniversary edition – stylish and durable storage.

Good to know

• Mirror or prism? As a guide, Baader recommends prisms for telescopes of about f/6 to f/7 or slower, and the BBHS® diagonal mirror for faster optics. We are happy to advise you.
• Optical length 112 mm: the diagonal mirror is longer than the diagonal prism (85 mm) and needs correspondingly more focus travel.
• The image is upright but mirror-reversed – as with any diagonal mirror.
• If the factory collimation is altered, the warranty on the collimation is void (the rest of the warranty remains unaffected). In case of deviations, first rule out other causes such as a tilted focuser.
• The anniversary edition is limited. Alongside the diagonal mirror, a BBHS® diagonal prism is also available in the 60 Years Vantablack® Edition.

Technical data

Scope of delivery

• Baader 2" BBHS® diagonal mirror – 60 Years Vantablack® Edition
• 2" ClickLock® eyepiece clamp
• 2" nosepiece to 2"/SCT with safety kerf (BP#2408156)
• 60th anniversary collector's edition beechwood case