FEATURES:

• Non-cementing optical substrate coating
• Electron-beam gun evaporation with Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL(central wavelength) no deviation affected by temperature change
• Planetary rotation system offers precision and homogeneity of coatings ensuring high value on transmission of pass-band and Optical density of off-band
• Ultra-thin filter cell minimize vignetting by maximize possible clear aperture (clear aperture is 26mm for 1.25”; 45mm for 2”)
• Aerometal Material, Precise CNC Machining, Sand Blasting Process, Black Anodized Finish, Extinction Treatment to Prevent Reflection, Laser Engraving No Fading.

DESCRIPTION:

Narrowband H-beta filter is designed for nebula observation allowing 12nm bandwidth of light centered on a wavelength of 486nm through, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. sky glow). H-beta emits 486nm and it is a blue-colored filter.

APPLICATION:

• Use with a large aperture telescope under clear and dark viewing conditions with good seeing
• Suitable for viewing on the faint and elusive Horsehead Nebula and California Nebula
• Narrowband filter do not eliminate the effects of light pollution or increase the object’s brightness. In many cases, they increase the contrast between nebula and night sky, not brightening the nebula.

Size

Standard 1.25” & 2” | Round 36mm Unmounted

Note : This filter is not designed for sun observation. DO NOT LOOK AT THE SUN WITH THIS FILTER. You would be BLIND if you fail to observe the warning.

Note: For Solar observation use high quality solar film ie BAADER Solar film or Solar filter along with this filter.