Multi-Band (Dual/Tri/Quad-band)

L-Quad Enhance Filter (L-QEF) 

L-Quad Enhance Filter (L-QEF) is a quad bandpass light pollution suppression filter for colour cameras. It effectively suppresses the transmission of light pollution wavelengths, especially light pollution generated by artificial lighting (including mercury and sodium lamps), as well as the effects of natural skylight-induced effects on the shot, thus effectively enhancing the contrast and details of the celestial bodies, and making the objects more distinct and stereoscopic. This filter provides better color balance while improving resistance of light pollution. L-QEF can be used for both wide field astrophotography, such as the Milky Way in Summer and Winter, and deep sky objects such as nebulae, galaxies, star clusters, and so forth; It allows you to save a lot of time during the shooting process and get better results at the same time. The design of quad bandpass maximises the colour balance of nebulae, galaxies and other broadband spectral targets.

Optolong L-eXtreme Dual Bandpass Light Pollution Reduction Imaging Filter - 1.25"

Optolong L-Ultimate 3nm Dual-Band Filter - 1.25" 

The L-Ultimate is a 3nm dual band filter designed to drastically reduce the effect of light pollution. The 3nm isolates the nebulae's emissions into H-Alpha (red) and OIII (green-blue). It blocks light pollution, maximizes the signal from nebulae, and darkens the sky background. It also blocks artificial light from mercury vapor lamps, high and low pressure sodium vapor lights, and unwanted natural light caused by the emission of neutral oxygen in our atmosphere, maximizing the transmission of the main emission lines of the nebula in OIII (496nm and 500nm) and H-alpha (656nm). Used with DSLR, color/MONO CMOS and CCD, this filter is suitable for telescopes with an f-ratio of f/4 or higher (slower).

Optolong L-eXtreme Dual Bandpass Light Pollution Reduction Imaging Filter - 2"