Alstar 2" Narrowband NBPF Hydrogen-a 12nm Filter - Enhances The Contrast Between Object and Sky - Allows You to Take Images Even Under Urban Skies

Alstar 2" Narrowband NBPF Hydrogen-a 12nm Filter - Enhances The Contrast Between Object and Sky - Allows You to Take Images Even Under Urban Skies

• Metal filter cell threads directly into the 2 inch barrel of your telescope eyepiece; Mounted in a nicely anodized housing
• The Alstar H-aplha cut off filter enhances the contrast between object and sky; allowing you to take good quality images even under urban skies
• Young stars embedded in the bright red of a nebula: an H alpha filter is the expert if you want to capture hydrogen nebulae in all their glory
• With a bandpass of 12 nm; only light above 660 nm is allowed into your camera whether under dark skies or under the sky glow of a city; That means the filter also blocks the infamous stray light and light from mercury and sodium vapour lamps
• Astrophotography under a light polluted night sky can be difficult; The solution is an H alpha filter; The Alstar H alpha cut off filter works to filter out a large part of this light pollution