Telescope-Accessories-Optolong L-Pro 2″ Mounted Filter

The Perfect Answer for Combatting Light Pollution!

With light pollution becoming an ever increasing issue, the addition of a light pollution filter is a great way to overcome the challenges presented with urban stargazing. This Optolong L-Pro helps take your astronomy sessions to the next level by effectively reducing light pollution from artificial and natural sources, greatly enhancing nebulosity and improving detail! To be used for visual astronomy or for astrophotography, views through your eyepiece are sure to amaze, while stunning detail comes to life within your images.

This Oplotong L-Pro reduces the transmission of wavelengths from mercury vapor lamps, both high and low pressure sodium vapor lights, and even natural light from skyglow. This light blocking nature improves contrast and clarity, making faint deep sky objects much more pronounced within your eyepiece and images. By selectively allowing key emissions from nebulae through such as OIII (496nm and 500nm), H-beta (486nm), NII (654nm and 658nm), H-alpha (656nm), and SII (672nm), this filter provides beautiful color balance and trivial color cast. With the ingenuity from Optolong, you can expect exceptional performance, allowing urban stargazers the chance to witness vibrant, breathtaking details of the night sky!

A High Performance Astrophotography Filter of the Utmost Quality

Let’s Take a Deeper Look!

What sets one filter apart from another? Which filter is best for me? When developing a filter, manufacturers provide a chart that represents the wavelengths permitted through this filter. This gives insight into the filter’s performance, and what it can help you achieve. So, how exactly do I read a transmission chart? Our team has put together a comprehensive article, to help you understand the fundamentals on How to Read a Transmission Chart. Check out the article and feel more confident about choosing the right filter for your needs!

Improved Detail, Even from the City

By reducing transmission from light pollution, this Optolong L-Pro helps level up your astronomy sessions. Whether utilizing for visual observing or for astrophotography, this high quality filter brings out the subtle structures and textures on a wide variety of deep sky objects. Read on as we delve deeper into the incredible features of this Optolong L-Pro!

Light Pollution No More!
As opposed to harsh narrowband filters that cut out an excessive amount of light, this L-Pro features precision off-band blocking in the major emission lines of artificial light pollution (i.e. Na 589nm, Hg 435nm and 578nm), while still allowing light from faint deep sky objects through. Suitable for reflection nebulae, emission nebulae, galaxies, and star clusters, this Optolong L-Pro provides a wide variety of imaging opportunities. Its selective nature highlights the intricate structure of the Orion Nebula, provides beautiful resolution of the Hercules Cluster, and reveals the radiant glowing gas of the Pleiades Open Star Cluster—all from light polluted environments! As seen in this comparison image, taken with a DSLR and a clip in version of the L-Pro, the Milky Way is captured with increased clarity, with the glow from the city greatly diminished. No matter what you choose to image or observe, the Optolong L-Pro is a perfect addition to your astrophotography or stargazing setup.

Effortless Compatibility
This Optolong filter is 2” in diameter, providing consistent, edge-to-edge illumination across full frame sensors and large 2” eyepieces. It’s housed within a filter cell with M48 x 0.75 threads for seamless integration into your filter drawer, filter wheel, or a direct connection to your telescope or eyepiece. This design makes it compatible with just about any system, offering ease of installation and providing a secure, stable fit.

Premium Construction
Composed of Schott B260 substrate from Germany and featuring multiple layers of anti-reflection, non-cementing coatings, this Optolong L-Pro offers outstanding performance. These coatings are applied via electron-beam gun evaporation with Ion-assisted deposition, providing high transmission at the major nebula emission lines while efficiently blocking off-band wavelengths. The high surface quality of 60/40 ensures pristine views and images, while the CNC machined, all metal filter cell provides exceptional durability. The surface of this filter cell is black anodized and includes laser engraving to prevent fading. The included plastic case with high pressure EVA lining protects your filter when not in use.