Optec #47B Blue Glass Filter Mounted in 48mm Metal Threaded Cell for 2" Eyepiece or NextGEN Telecompressors

• All of the NextGEN series reducers accept the standard 48 mm filter thread commonly referred to as 2-inch filter size. The filters from Optec are of the highest photographic quality and available with many varied transmission characteristics to enhance contrast, reduce background illumination, or block certain wavelengths.

Since the Optec filters have threads on only one side, they can not be stacked. Before the availability of cheap and good dichroic filters, this #47B blue filter was used for RGB imaging to pass the blue band. Low transmission in the blue and very transparent in the IR makes this filter useful only for special projects.