Starfield 0.8x Reducer & Field Flattener 2" Body 38mm Clear Aperture Fully-Multi-Coated Optics M42 T-Thread for DSLR Optional M48 Threaded Adapter 55mm of Backfocus The Starfield 0.8x Reducer doubles as a field flattener for f/5.5 or longer refractors. This high quality optical accessory is a must for those imaging with a DSLR or dedicated astronomy camera. It has multi-coated optics that are housed in a hard-anodized aluminum body to reduce weight. The M42 connection is removable and can be replaced with an optional M48 threaded adapter for full frame cameras. Providing pinpoint stars across the field of view, the Starfield reducer/flattener decreases the effective focal length of your imaging refractor by 0.8 times. The Starfield 0.8X reducer is designed to be used with a refractor that has a focal ratio of at least f/5.5 and has a 2" focuser. It is perfect for DSLR use and requires 55mm of back focus. No additional extension rings are required. A large, clear aperture of 38 mm removes the chance of vignetting when used with APS-C and smaller sensors. This reducer/flattener has an 42 mm adapter that can be removed and replaced with an optional M48 adapter. There is a built-in M48 filter thread; perfect for your favorite light pollution filter. Remember that you'll need a standard M42 t-ring for your camera model. For Canon cameras, the depth should be 11 mm, and for Nikon cameras, it should be 8.5 mm.
