Baader Flip Mirror II (BFM)

Baader Flip Mirror (BFM) II Star Diagonal

Various ports – variable work

Telescope auxillary instruments cover a wide range of interests, from a sole eyepiece, via camera use, to high end spectroscopy. Unfortunately every telescope just features one exit port. This causes relentless manual exchange of parts in the dark, causing huge time loss, wear on the parts - and "nerves". And whenever you start controlling your telescope remotely - the single port becomes a painful reality.

Improving workflow, especially during astrophotography is the goal set out for the BFM II. This is not just a simple flip mirror but much more, as there are three ports to be put into action. The BFM II also enables the precise adjustment of all light paths.

BFM II makes your single telescope port variable – to suit your various interests.

The FlipMirror II Star Diagonal allows a variety of permanent adaptations to your telescope 1 . Use the rotary knob 2 to switch between the rear port 3 and the top port 4; you can use an optional toothed belt to operate it with a motor (not included). An autoguider or a calibration lamp can be connected to the bottom port 5.

Baader-FlipMirror II Star Diagonal (BFM II) offers you three ports:

• Straight-through (S52, M48 and T-2 on both sides) for full-frame camera, spectrograph, or other instruments
• Adjustable T-2 thread on top for eyepiece clamps, video modules (up to 32 mm image circle) or even a binoviewer
• Bottom flange for the optional Off Axis Guider for Baader FlipMirror II (BFM-OAG) (#2956951) or for an optional calibration lamp for quick calibration of spectra without removing the spectrograph.

The rotatable M48 connection rings are made of hardened, stainless steel on front and rear. They are adapted backlash-free to the BFM housing, so that they can be fixed in the optimum position to rotate any accessory around the optical axis. The BFM II is compatible with a large number of adapters from the Baader Astro T-2 system, the M48 system and the UFC system (Universal Filter Changer).

General Function of the FlipMirror II Star Diagonal

The heart of the BFM II is a precise surface-mirrored flip mirror with multi-layer Al coating, which can be used as any regular high-end star diagonal for visual observations and for high-resolution images with cameras with small pixels. In addition, the BFM II lets you switch between a straight light path (Position A) for a camera or other measuring instruments and an angled light path (Position B), e.g. for an eyepiece. The following figure shows how it works. In addition, a calibration lamp for spectrographs or an Off-Axis-Guider pickoff-prism (that is not affected by the mirror position) can be connected at the AUX-port on the bottom. The back of the flip mirror is also Al coated and masked to direct the light of an optional calibration lamp onto the slit of a spectrograph.