The Optec Lepus ACF 0.62X is a 4-element telecompressor designed by Optec engineers to work with the Meade ACF series telescopes. with a 2″ 24tpi threaded collar it will screw directly to the rear cell of Meade ACF telescopes. Also known as a focal-reducer, the Lepus provides a 0.62X reduction of the telescope’s effective focal length. Optec Lepus ACF 0.62X works well with most mid-size CMOS cameras and Digital SLR cameras having sensor diagonals up to 28mm.
Lepus is optimized for 100mm of distance between the last lens surface and the image plane. Measured from the telecompressor flange, this distance works out to 105mm as shown below. Assuming a native focal ratio of f/10, the Lepus 0.62X will reduce the effective focal ratio to approximately f/6.2. Shifting the image plane outward will provide additional reduction but a loss of star quality at the edge of the images. The optimal distance for most SCT’s is 100mm with the exception of the C9.25 EdgeHD SCT.
Designed for Midsize CMOS and DSLR’s
Lepus will deliver a fully unvignetted image 22mm in diameter, but will provide well-corrected images out to 28mm with a small amount of light fall-off. Flat fielding is recommended for best results.