The Ultra WideField 0.7XL is a coupler from Optec and is designed specifically to speed up the focal ratios of highly corrected telescope systems. This design assumes that the image formed by the telescope is reasonably flat and aberration free. If so, the resulting image will also be highly corrected and nearly parfocal with the original image. Optimized for an f/8, the Ultra WideField 0.7XL will work for any focal ratio in the range of f/5.6 to f/20. The field is highly corrected up to 18mm in diameter and would work well even with larger fields with only slight degradation near the corners.
Like the other reducers in the NextGEN series, all surfaces have a broadband multilayer coating optimized for the 450 - 650 nm pass band of the optic. Filter mounted in front as with the IFW are compatible. In fast systems, it is always better optically to mount the filters in front of any reducer optic to keep the incoming rays closer to being normal (collimated) to the filter surface.
The Ultra WideField 0.7XL was redesigned and improved in late 2006 and now has a much longer back-focus distance and uses the same mounting plate adapters as the 0.33X and 0.50X models. This allows use of this reducer with SBIG cameras having the CFW-8/10 filter wheels mounted.
- TCF-S focuser,
- Any 2-inch focuser or receiver.
- NextGEN Camera-specific mount. See this table for currently supported cameras.