Baader Off Axis Guider for Flip Mirror II - BFM-OAG

Baader Off-Axis Guider for Baader FlipMirror II (BFM-OAG)

This off-axis guider fits especially for the Baader FlipMirror II star diagonal (BFM II) #2458055. It is connected to the lower port of the BFM II (19 mm plug diameter) and always supplies a autoguiding camera with light, independent of the mirror position of the BFM II. To connect to a telescope without BFM II you need the off-axis guider for RCC (RCC-OAG) # 2956950 with T2 connector instead.

You can attach the off-axis guider for Baader FlipMirror II (BFM-OAG) directly to the Baader FlipMirror II star diagonal (BFM II). For mounting, remove the flat intermediate ring as shown in the illustration on the right so that the prism projects further into the housing.

Further information from the manufacturer

The prism looks under the mirror so that it can also be used with the mirror flipped down, for example to guide a planetary camera connected at the top. When the mirror is flipped up, the rear camera should be aligned as usual so that the prism is under the long side of the sensor.

To bring the guiding camera connected to the off-axis guider into the same focus position as the cameras/eyepieces connected to the FlipMirror, you have several options. For the cameras connected to the FlipMirror, you can use T2 or M48 spacer rings as usual. To position the guiding camera higher above the BFM-OAG, you can extend the 1.25" receptacle of the autoguider with one or two DT-4 extension tubes #1905130 and fix it in height with the FR-4 locking ring #1905131.

If you use the off-axis guider for Baader FlipMirror II and a guiding camera whose image plane is at the upper end of the off-axis guider (that means: without additional back focus), the image plane of the camera and the eyepiece is about 24 mm behind the two T2 threads of the BFM II. A CCD camera with a short back focus, for example, can be adjusted to this distance with a VariLock 29, as can the Polaris I reticle eyepiece when connected directly to the VariLock 29 via T2. Thus a very short adaptation is possible.

If you are using a DSLR via a T2 adapter, or an eyepiece clamp for the search eyepiece, you will need more back focus. In this case, the guiding camera must be placed at a greater distance from the BFM II. The easiest way to do this is to use the DT-4 extension tube # 1905130 with an overall length of 18.5 mm. It has the diameter of 1.25" eyepieces and is screwed into the 1.25" filter thread of the guiding camera. With one or two of these tubes you can place virtually any camera over the off-axis guider so that it is parfocal with the imaging camera.