Optolong L-Ultimate 2" Light Pollution Dual Band Filter
Optolong L-Ultimate 2" Light Pollution Dual Band Filter
The Optolong L-Ultimate is Optolong's newest and NARROWEST dualband filter. This is an exceptional choice for amateur astrophotographers who use one shot color (OSC) cameras for deep space imaging. This 3nm dualband filter will cut through the light pollution and provide high contrast data for you to process and enjoy.
The L-Ultimate from Optolong is a 2" threaded light pollution filter. While the L-Ultimate is similar to Optolong's L-eNhance and L-eXtreme filters in that it is a dual band filter that allows the transmission of Oxygen III and Hydrogen Alpha wavelengths, the L-Ultimate differs in that it only allows a 3 nm badwidth at both the H-Alpha and OIII transmission lines. Compare this to the 7 nm of the L-eXtreme.
Transmission on this dual-narrowband filter occurs at 500.7 nm (OIII) and 656.3 nm (Ha), both with a 3 nm bandwidth. All other light is blocked, allowing greater capture of nebulae emissions at a greatly enhanced signal-to-noise ratio. This filter is particularly helpful in heavily light polluted areas.
Compatible with DSLR and color and mono CMOS and CCD cameras. This filter can be used with scopes that have a focal ratio greater than f/4.
Narrow, 3-nanometer Transmission
This filter from Optolong eliminates light at all wavelengths other than the Oxygen III and Hydrogen Alpha. Transmission for this filter occurs at 500.7 nanometers (OIII) and 656.3 nanometers (Ha), with a very narrow 3 nm bandwidth at both emission lines. Light from mercury and sodium street lights are suppressed, as well as unwanted natural light.
A Filter of Great Quality
The L-Ultimate filter from Optolong sports a number of high quality manufacturing features. Offered in a 2" threaded form factor, this filter is compatible with all 2" accessories with accommodating threads. Additionally, the glass has a very small optical thickness, at 1.85 mm.
Reduce or Eliminate Haloing Effects
Tests on the bright star, 52 Cyg, show that there is virtually NO halo effects! This is a star that is notorious for giving amateur astrophotographers with lesser filters, a bit of trouble.