This economical 2" dark green filter makes an excellent moon filter as it reduces the moons glare by only transmitting about 24% of the light. This filter threads into your 2" star diagonal. You can then use it with all of your eyepieces without having to move the filter from one eyepiece to the next. So when you are ending your visual observing session and ready to sacrifice your night vision by looking at the moon, thread in the filter and enjoy cruising above the surface of our nearest neighbor.
While the 58A is also used as a planetary filter to enhance the cloud cover on Venus, Jupiter and Saturn, this filter significantly darkens the view. So we do not recommend it as a planetary filter for Apo refractors under 152 mm.