TPO #21 Orange Filter & Case - 1.25" Round Mounted

#21 Orange Filter:
  • Can Reduce or Block Blue-Green Wavelengths
  • Sharpens Boundaries of Yellow-Orange to Blue-Green areas
  • Case Included
  • Fits most 1.25" Eyepieces


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  • Regular price $8.95

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TPO #21 Orange Filter & Case - 1.25" Round Mounted

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. All eyepiece filters are threaded to fit most 1.25" eyepieces and offer a full 26mm clear aperture. Comes with a hinged, plastic case to keep your filter safe and clean when not in use.

#21 Orange (46% transmission) reduces or blocks transmission of blue-green wavelengths. Use on Jupiter and Saturn to enhance detail in the belts and polar regions. Sharpens boundaries between yellow-orange areas and blue-green regions on Mars, resulting in a darkening of edge-detail in the maria.


TPO Product Number: OS-F21



Filter TypeOrange
Free ShippingYes
Warranty2 Year Warranty
Wratten #21