Alstar 2 Narrowband O-III Filter - Enhance Contrast In Dark Skies

Function 2 Can be used with all 1.25 inch eyepieces and other accessories. Function 1 Completely blocks virtually all other visible wavelengths of light. This item: 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 Get it as soon as Sunday, May 4 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 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 Telescope Filter Alstar 2 Narrowband O-III Filter - Enhance Contrast In Dark Skies Ir Filter Function 2 Can be used with all 2 inch eyepieces and other accessories. Function 1 Comfortably observing the moon, or stacking with other planetary filters. Freedom To Choose!