Used Generic Planetary Filter Set, 1.25"

Condition:

This is a set of generic planetary filters in excellent condition with clean optics. This includes a jewel case that fits all 4 filters, and an instruction sheet describing which filter to use on which planet. 

Description:

The #23A Light Red Filter is another great filter for use on Mars, Jupiter, and Saturn, but because of lowered light transmission, it may not perform well for 6" and smaller telescopes. It carries out many of the same functions as the #21 and the #15, but with more contrast, bringing out marginally defined blue-green surface detail.

The #56 Green Filter is marvelous for increasing the contrast in Mars' polar ice caps as well as yellow-tinted Martian dust storms. It also does a reasonable job of increasing the contrast of cloud patterns on Venus. This filter strongly rejects red and blue wavelengths and increases the contrast of these regions in Jupiter's atmosphere as well as in the cloud belts. It can also enhance the white portions of Saturn's cloud belts and polar regions. The green filter is useful for enhancing lunar detail. It also reduces blue-sky brightness here on Earth.

The #80A Medium Blue Filter is one of the most commonly used filters amongst the entire spectrum of filters. It is perhaps the best filter for the study of detail on Jupiter and Saturn. It enhances the contrast of rills and festoons in Jupiter's cloud belts, as well as details of the Great Red Spot. It brings out detail in Saturn's belts and polar features. The filter is very useful on Mars in showing the high clouds and ice caps, and is especially useful during the violet clearing.

The #12 Yellow Filter increases the contrast of blue and green areas on Mars, thus darkening the Maria, oases and canal markings, while lightening the orange-hued desert regions. It sharpens boundaries of yellow dust clouds and the blue clouds in the Martian atmosphere and is thus a favorite for viewing the red planet.