***** **********Best Quality Guranteed. *****85mm focal length, reduction factor of about 0.5X, depending on spacing. 0.5 x focal reducer effectively halves the focal length of a telescope, enabling lower magnification. *****Mounting threads - 1.25" filter thread ( 28.5 x 0.75 MM) on one sides, the opposite end of this adapter has a C-Mount (1 inch diameter with 32 threads per inch) standard for C or CS mount CCTV type cameras with telescopes. *****A wider field of view, and shorter exposure times for astrophotography. 2 lenses for better correction - cemented together and coated, black-anodized aluminum housing.
*****Free light transmission - 22.5 mm lens aperture. Can be used with additional spacers (available separately) to achieve further focal reduction. *****Intended for use with with longer-focal-ratio telescopes and eyepieces of narrow to moderately-wide apparent fields of view.