美國Celestron F6.3高級減焦镜

The Reducer Corrector lets a Schmidt Cassegrain Telescope become a wide-angle telescope with a nice flat image and no residual color at 10% of the cost of a second scope.

This device is an accessory for use with Schmidt Cassegrain Telescopes. It is intended to convert the telescope into a shorter focal length wide-angle field of view telescope.

Celestron advertises the f/6.3 focal reducer as being the one accessory needed to turn one of their f/10 Schmidt Cassegrain Telescopes ( SCTs ) into another telescope. In fact, they even claim its potency is so great that a shorter focal length version of their telescopes is redundant, so they don't make them since one of the f/10 telescopes can be turned into the other telescope at will at 10% or less of its cost.