Eyepiece filters are an invaluable aid in lunar and planetary observing. They reduce glare and light scattering, increase contrast through selective filtration, increase definition and resolution, reduce irradiation and lessen eye fatigue.
TPO filters are made of high quality, solid plane parallel glass with excellent homogeneity. They are anti-reflection coated to prevent glaring and ghosting. This eyepiece filter is threaded to fit most 1.25 inch eyepieces, and comes with a hinged, plastic case to keep your filter safe and clean when not in use.
The #15A Dark Yellow Filter has a transmission of 67%, and is a good general-purpose filter for telescopes with less than 4.5 inches of aperture (114mm). The #15 filter will improve the contrast of features on the Moon It will also help you see the equatorial belts on Jupiter and Saturn, clouds and the polar ice caps on Mars, and the dusky detail on Uranus and Neptune.
TPO Product Number: OS-F15