Optolong H-Alpha 7nm Imaging Filter - 1.25" - HA-7-125 Lunt Ha Solar Filters 5kg)(Optional) Operation temperature -20ºC ~

5kg)(Optional) Operation temperature -20ºC ~ 40ºC (hand controller -10ºC ~ 40ºC) Warranty Two year limited * 200mm

solar and lunar)

travel/camping life

and it filled the void for a lack of high-quality

Sensor Size:  14

Optolong H-Alpha 7nm Imaging Filter - 1.25" - HA-7-125 Lunt Ha Solar Filters 5kg)(Optional) Operation temperature -20ºC ~The Optolong H Alpha 7nm Narrowband Imaging Filter is the popular filter allowing 7nm bandwidth of light centered on a wavelength of 656nm 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. skyglow). Better choice of