Nebula filter for increasing contrast; also suitable for use with smaller telescopes
Many objects only first become visible at all when using an UHC filter; but also; highlights such as the Orion; Lagoon or Swan nebulae; show a whole new side to them
Can be used at both light-polluted and dark sky sites; blocks the light from mercury and sodium-vapour lamps
85mm focal length and reduction factor of about 0.5x that depend on spacing; 0.5x focal reducer effectively halves the focal length of a telescope for enabling lower magnification;
Mounting threads: 1.25 inch filter thread or 28.5x0.75 mm on one sides; the opposite end of this adapter has a C-mount that is 1 inch diameter with 32 threads per inch standard for C or CS mount CCTV type cameras with telescopes;