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SBIG AFW Filter Wheels are fast and quiet, and are designed to be compatible with our full line of SBIG cameras.  Two size formats are available: Large Format AFW wheels are ultra-thin, minimizing back focus distance. The standard version, which accommodates filters ranging from 1 mm to 3 mm thick, uses only 0.55" (14 mm) back focus. The tall version, which accommodates 5 mm thick filters, uses only 0.65" (16.5 mm) back focus. Ultra Large Format AFW wheels are designed for the new Aluma AC461 camera.  Featuring dual carousels each holding six 65 mm filters, the wheel uses only 1.1" (28 mm) of back focus.  Coming soon - advance ordering available.  Compact Format AFW wheels are a lower-cost option for our compact Aluma CCD and STC-428 cameras.  For users needing more filter slots, an adapter is also available to interface our compact format cameras to a Large Format AFW-16-36R.