Optolong 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 area with heavy light pollution.
Unlike other light pollution filter UHC and CLS, L-Pro is 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.

Main Use and Performance

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 filter 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.

WARNING: The filters of Optolong are not designed for sun observation. DO NOT LOOK AT THE SUN WITH OPTOLONG FILTER.

You would be BLIND

if you fail to observe the warning.

2. New Frame of Sony-FF Clip-in Filter Specifications

3. Spectrum for Reference

4. New Frame of Optolong Sony-FF Clip Filter

Due to limit lens resource, we only test the popular lens in market. If any available lens, feel free to contact Optolong customer service

staff. We appreicate for your valuab testing information.

Video Direction

Kindly click below image to review video about how to install and remove the filter at Optolong YouTube channel.

6. Packing:

Outer Box: silve box

Plastic Box: PP material

Lining: imported high pressure white EVA material

Shipment kit of new frame Sony-FF L-Pro clip: L-Pro filter, Trangle piece and installation instructions

Comparason image was shot by Arnaud Besancon

All the pictures have been realised with 5D3 Astrodon modded and Samyang 24mm F1,4 at F2, 13s exp. time,3600 isos.

All the pictures are raw,without post-process
.

IV M42 compare image by Luca Fornaciari Astrophotography