Baader Planetarium 2" Prism Star Diagonal with BBHS Coatings & 2" ClickLock Eyepiece Clamp

Baader 2" 90º Prism Star Diagonal with BBHS Coatings

• 2" Prism Star Diagonal features a 90º right angle prism made with Baader's famous BBHS multi-coatings yield bright images with beautiful contrast.

• CNC-milled black aluminum housing with adjustable wedge for adaptation to individual optical systems.

• The 2" clicklock eyepiece holder and 2" nosepiece can be removed, allowing you to adapt the diagonal base to the Baader Clicklock System if so desired.

More About the Baader 90º 2" Prism Star Diagonal

The star diagonals with prisms from Baader Planetarium offer the highest mechanical and optical quality and are part of a fully modular system. The BBHS ® prisms can also be screwed directly onto the focuser or accessories to provide an especially tilt-proof and short optical path connection. Even a 2" filter can be inserted permanently into the eyepiece-side of the 2" nose-piece, so that you can still use the 2" filter thread on the telescope side as usual.

In contrast to simple prisms, Baader prisms use an additional BBHS ® silver layer that is elaborately sealed against corrosion. This layer is responsible for the outstanding brilliance and richer colors compared to simpler prisms. BBHS ® is an abbreviation for Broad Band Hard Silver; the silver layer is stabilized long-term by a hard protective coating.

BBHS ® provides a much broader spectral range with 98-99% reflection from just above 390nm to 2000nm, and it maintains high reflectivity even with varying viewing angles – the silver layer produces no stray light whatsoever. A trained eye will especially see a greater color range when using short focal length APO refractors. Particularly in planetary observation at the highest magnifications, a noticeable increase in color intensity can be easily observed compared to all previous coatings. Additionally, a clear increase in contrast is noticeable due to the absence of any stray light. Together with the CNC-milled aluminum housings, this ensures extremely fast temperature adaptation and image stability. As a general guideline, prisms are recommended for telescopes with a focal ratio of about f/6 to f/7 or slower, while BBHS ® mirrors are preferable for faster optical systems.

In addition to the sealed BBHS ® rear-surface coating, the prisms feature the proven Phantom Coating ® Group anti-reflection treatment.

The precisely fitting 2" ClickLock ® eyepiece clamp securely holds even heavy accessories with a simple 20° twist. By cleverly using leverage, the clamping force is multiplied many times. The inserted accessory is held on three sides, similar to a quick-release chuck, preventing any tilting movement. Every eyepiece or measuring device is automatically aligned parallel to the optical axis – even in the case of diameter tolerances.

The BBHS ® Prism is mounted in a CNC-machined aluminum housing and rests stress-free on an adjustable cradle. Just like a high-quality refractor objective, the prism can also be collimated. This allows the realization of fully adjustable systems, for example for the construction of binocular telescopes. As with a premium refractor, you will not need to change the collimation during normal use: the 3-point alignment is set at our factory so that the image shows no noticeable rotation around its center when the star diagonal is rotated by 180° in a correctly aligned eyepiece clamp. Optical and mechanical axes are perfectly matched on our optical test benches. Therefore, make sure to rule out all other potential sources of error – such as a tilted focuser – before adjusting the collimation.

When a BBHS ® Prism leaves the factory, the optical and mechanical axes are aligned rotationally symmetrically with each other on the optical bench. Please note that once the collimation is changed, the warranty on the factory collimation of the BBHS ® prism becomes void. All other warranty coverage remains unaffected.

Please Note: This diagonal does not come with a 1.25" Adapter. If you wish to use 1.25" eyepieces or other barreled accessories in this 2" Star Diagonal, you will need to acquire a 2" to 1.25" Adapter.