TPO #38A Dark Blue Color Filter & Case - 1.25"


#38A Dark Blue Filter:

  • Great for Planetary Study
  • Strong Rejection of Orange and Red Wavelengths
  • Increases Contrast between Red and Blue Structures and Details
  • Size: 1.25 inches
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  • Regular price $8.95

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TPO #38A Dark Blue Color Filter & Case - 1.25"

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" eyepieces, and comes with a hinged, plastic case to keep your filter safe and clean when not in use.

#38A Dark Blue (17% transmission): A popular filter for the study of Jupiter's disc, owing to the filter's strong rejection of orange and red wavelengths. Increases contrast between the reddish belt structures and enhances detail of the Red Spot. Also useful for the study of isolated phenomena, such as dust storms, on Mars, as well as the belt structure of Saturn. Increases contrast of subtle cloud markings on Venus.


TPO Product Number: OS-F38A


Filter TypeBlue
Free ShippingYes
Warranty2 Year Warranty
Wratten #38A