Set #2 (4 filters): #11 Yellow-Green; #25A Red; #47 Violet; #82A Light Blue.
<B>#11 Yellow-Green (78% transmission) -</B> Contrasts well with the red and blue characteristics of surface features on Jupiter and Saturn. Darkens the maria visible on Mars, and clarifies the Cassini division in Saturn's rings.
<B>#25A Red (14% transmission) -</B> The #25A filter strongly blocks the transmission of blue and blue-green wavelengths, resulting in very sharply defined contrast between, for example, blue-tinted cloud formations on Jupiter and the lighter-toned features of the disc.
Also useful for the delineation of the Martian polar ice caps and maria. Because of its relatively low total light transmission the #25A filter should be employed on telescopes of 8" aperture and larger.
<B>#47 Violet (3% transmission) -</B> Strongly rejects red, yellow, and green wavelengths; useful for the study of Martian polar cap regions and for the observation of occasional phenomena in the upper atmosphere of Venus.
Enhances contrast between the rings of Saturn. Use only on telescopes of 8" aperture and larger.
<B>#82A Light Blue (73% transmission) -</B> Useful on the Moon, Mars, Jupiter, and Saturn, this subtle pale blue filter enhances areas of low contrast while avoiding significant reduction of overall image brightness. A valuable filter to piggyback with other filters.