The Universal Filter Changer, UFC: The Baader UFC system is a filter drawer suitable for a variety of telescope and camera systems with a sufficiently large connection diameter, which is extremely short-build at the same time but also accommodates filter sizes up to 50x50mm vignetting-free. These properties are a condition to the new, fast optics such. Hyperstar's EdgeHD telescopes and Celestron's new RASA devices, as well as all other Prime-Focus astrographs , can be operated with suitable filters on which a regular filter wheel would shade off too much of the front opening. In addition, prime-focus optics are inevitably equipped with a very short back focus and require a particularly space-saving filter drawer.
The UFC system can connect almost everything with everything by acquiring the same filter base housing and then simply selecting the necessary front and back plate of the UFC together with the spacer rings as required by the respective chip spacing. For this purpose, Baader offers a set with matching UFC extension sleeves, as well as a 15mm to 20mm infinitely adjustable S70 VariLock extension to keep the distance between the filter and the image plane as short as possible. All components are optimized in order to obtain the greatest possible passage in front of the actual filter drawer and nevertheless to be able to precisely set the appropriate distance between the telescope and the chip. The filter drawer itself sits in each case as close as possible in front of the camera, shading by the filter is minimized.