Astromania Telescope Filter, 2 inch Multi-Narrowband Galaxy Nebula H-Beta Filter for Astronomy Telescope, Metal Frame Telescope Accessories Narrowband Cuts Light Pollution Filter
Product Description
Astromania Telescope Filter, 2 inch Multi-Narrowband Galaxy Nebula H-Beta Filter for Astronomy Telescope, Metal Frame Telescope Accessories Narrowband Cuts Light Pollution Filter
- Filter with metal mount 2 inch and M48 filter threads on both sides
- Executes with a transmission of over 90 percent and completely rejects light pollution
- The high optical quality of the Astromania filters guarantees no loss in sharpness or contrast
- Have extremely high transmissions while completely rejecting light pollution as well as the important blocking of longer wavelengths
- Substrate is fine-optically polished plane parallel to deliver a smooth and accurate 0.25 wavefront over the entire surface
One of our High Transmission (HT) precision range of filters, this 2" H-Beta Filter is sure to impress on performance, quality and price. It comes with its own individual data sheet of performance - guaranteed! It is an extremely useful filter for observing the very feint nebulae. It has a very limited transmission range of 484 - 490nm (70%) and 478 - 483 & 492- 497nm (60+%). The very sharp cut offs only allow the hydrogen beta light that these feint objects emit to pass through. By cutting off almost all of the visual spectrum the filter effectively blackens the sky to make these objects show through. This filter is best used on large aperture telescopes (8" +) under very good seeing conditions and is an essential item for those astronomers who enjoy tracking down the most elusive of deep space objects. This is a filter for visual observational use.
