Alstar 2' Narrowband O-III Filter - Enhance Contrast in Dark Skies - Observe Clear Veil, Ring, Dumbbell and Orion Nebula, Among Many Other Objects
$70.79
$70.79
$
33
.99
$33.99
About this item
- Each Alstar 2 inch O III Filter is individually inspected and proudly inscribed with the percentage of light transmittance of the two O III emission lines
- Not only useful at light polluted sites; the contrast is also increased at dark sky sites; can be used with all 2 inch eyepieces; Filter made from high grade glass with dichroic interference and antireflection coatings
- Completely blocks virtually all other visible wavelengths of light so views of nebulas are optimized; Increases contrast through selective filtration Anti reflection coated to prevent glaring and ghosting
- Especially useful for large aperture telescopes through which the light of the Moon can be extremely overwhelming; Allowing just for the Double Ionized Oxygen lines between 496 nm to 501 nm to pass through at 95 percent
- 2 inch O III Filter greatly enhances contrast during visual observation of gaseous and planetary nebulae in all sky conditions; The 2 inch filter allows high contrast imaging even in areas with strong light pollution
