EXPLORE SCIENTIFIC OPTOLONG 2" L-Pro Deep-Sky Light Pollution Filter

The relentless spread or urbanization and its associated light pollution have become a growing problem for all amateur astro photographers. The current solutions to the problem can be expensive and might include the purchase of a monochrome camera, several types of narrowband filters and a filter wheel. Especially with inexpensive newtonian telescopes, double-lens ED refractors or even achromats, the L-Pro filters open up completely new possibilities for the capture of high-class astronomical images even out of the light polluted city. CMOS cameras can deliver images like monochrome cameras. This new generation of filters makes it possible to take amazing astrophotos directly from the light-polluted city with all its artificial light sources.

L-Pro is a multi-bandpass filter which offers better color balance by maximizing the transmission band. The balanced transmission allows astrophotos to be taken with minimal color cast to broadband emission objects such as galaxies, reflection nebulae and globular star clusters. L-Pro is the best choice for light pollution suppression.

L-Pro (L-Professional) filter is designed to improve the visibility of various deepsky objects. By selectively reducing the transmission of wavelengths of light pollutants, specifically those produced by artificial lightings including mercury vapor lamps, both high & low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow). Together with the highly transparent in main nebula emission lines at OIII (496nm and 500nm), H-beta (486nm), NII (654nm and 658nm), H-alpha (656nm) as well as SII (672nm), the filter is suitable for enhancing the contrast and details for both visual and photograghic purpose at sub-rural areas with heavy light pollution. L-Pro is a multi-bandpass filter which offers better color balance by maximizing the transmission band. The balanced transmission allows astrophotos to be taken with minimal color cast to broadband emission objects such as galaxies, reflection nebulae and globular star clusters. L-Pro is the best choice for light pollution suppression.

Suitable for visual observation and astrophotography. L-Pro filter has a very low transmission reduction rate against continuous spectrum space objects, and thus is quite effective in suppressing light pollution sources when shooting galaxies, reflection nebulae and globular star clusters. The same holds true for visual star observations. L-Pro filter alone can suppress infrared wavelength, and thus can be used at ease for ''L'' image shootings with CCDs. Light pollution filters 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.

L-Pro has a multiple anti-reflective coating on the optical substrate. The L-Pro filter uses a precision coating based on ion deposition coating technology. This ensures durability and scratch resistance as well as stability on the CWL (central wavelength), which is not affected by temperature changes. Absolute precision and homogeneity of the coatings as well as maximum values for transmission in the passband and optical density in the off-band range are guaranteed for all filters.