For sale in as-new condition, complete set of AP/Baader color filters.
Description from AP site below. Selling for $65, shipping inclusive to CONUS.
"These new premium 1.25" color filters (BPCF125) from Baader Planetarium feature high-transmission, plane-parallel, optically polished glass, multi-coated on both surfaces. True plane-parallel surfaces eliminate ghost images at the eyepiece. The fine optical polish allows the filters to be inserted anywhere in the optical path without introducing astigmatism and other defects. Thus they can be used with the Baader Giant Binocular Viewer or other similar products without concern about degradation of your image.
Filters come in the following colors: Red (610nm), Orange (570nm), Green (500nm), Yellow (495nm), Blue (470nm) and Blue-Violet (435nm). Transmission efficiencies for the Red, Orange and Yellow filters is approximately 95% within their passbands. Transmission efficiencies for the Green, Blue and Blue-Violet filters is approximately 65% at their center wavelength.
These filters can be used to bring out fine Lunar/Planetary detail while preserving maximum sharpness in the image. All filters have standard 1.25" eyepiece filter threads. Filters can be threaded together to allow stacking for narrower passbands. For instance, combining the Yellow filter with the Blue-Violet filter results in a very narrow dark green filter that transmits light only from 475nm to 500nm. Note: When stacking filters on eyepieces, be careful that the eyepiece barrel (with the filters attached) does not strike the mirror or prism of your diagonal.