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Optolong L-Pro Filter
Optolong L-Pro Filter
Optolong L-Pro Filter
Optolong L-Pro Filter
Optolong L-Pro Filter
Optolong L-Pro Filter
Optolong L-Pro Filter

Optolong L-Pro Filter

by Optolong
SKU OPT-10201
CA$199.00 - CA$377.00
CA$199.00
CA$199.00 - CA$377.00
CA$199.00
Price Match Policy!
  • Multi-Bandpass Light Pollution Suppression
  • Effective Spectrum from 380-750nm
  • Maintains Natural Color Balance on Broadband Targets
  • High Transmission on Major Nebula Emission Lines
  • Durable Ion-Assisted Multi-Layer Coatings
  • Surface Quality of 60/40 per MIL-O-13830
4 in stock
Qualifies for FREE Shipping in Canada on orders over $500.
  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Optolong L-Pro Filter

    The Optolong L-Pro Filter is engineered to reclaim the night sky from urban light pollution, operating across a 380-750nm spectrum and manufactured to a 60/40 surface quality standard. Its multi-bandpass design selectively blocks the most common wavelengths of artificial light while transmitting the light from deep-sky objects, resulting in images with dramatically improved contrast and natural color rendition.

    Suppressing Light Pollution Across the 380-750nm Spectrum

    The core function of the L-Pro is to isolate and reject specific emission lines from artificial light sources. It effectively targets the dominant wavelengths produced by mercury vapor, high-pressure sodium, and low-pressure sodium streetlights, which are the primary contributors to skyglow. By filtering these specific pollutants within its 380-750nm operational range, the L-Pro darkens the sky background without altering the light from your astronomical target.

    A Multi-Bandpass Design for Natural-Color Imaging

    Unlike more aggressive filters that can produce a strong color cast, the L-Pro uses a balanced, multi-bandpass approach. This design preserves the natural colors of broadband targets like galaxies, reflection nebulae, and globular clusters. For imagers, this means less time spent on color correction in post-processing and a final result that more accurately represents the true colors of the object.

    High Transmission for Key H-Alpha and OIII Emission Lines

    While excelling at broadband targets, the L-Pro also maintains high transmission for the most important emission nebula wavelengths. It passes critical lines including Hydrogen-alpha, Oxygen-III, Sulfur-II, and Hydrogen-beta. This allows you to capture the faint, glowing structures within objects like the Orion Nebula (M42) or the North American Nebula (NGC 7000) with enhanced contrast against the newly darkened sky.

    Built to a 60/40 Military Surface Quality Standard

    Each L-Pro filter is manufactured to a 60/40 surface quality specification according to military standard MIL-O-13830, ensuring clear, artifact-free images. The glass undergoes an ion-assisted deposition coating process, which creates a durable, scratch-resistant surface. This advanced coating technology also ensures the filter's central wavelength remains stable, preventing passband shifts due to temperature changes during an imaging session.

    Optolong L-Pro vs. UHC Filters: Choosing the Right Tool

    A common question is how the L-Pro compares to an Ultra High Contrast (UHC) filter. A UHC filter offers a more aggressive approach, providing maximum contrast on emission and planetary nebulae by isolating just the OIII and H-beta lines. This comes at the cost of nearly all star color and renders it ineffective for broadband targets.

    • Choose a UHC Filter for visual observing or imaging of emission nebulae from heavily light-polluted areas where maximizing contrast is the only goal.
    • Choose the Optolong L-Pro when your targets include galaxies, reflection nebulae, or star clusters, or when preserving natural color is a priority. It is the more versatile, "do-it-all" light pollution filter for modern color cameras.

  • What makes the Optolong L-Pro different from other light pollution filters?

    The Optolong L-Pro is a multi-bandpass filter designed for maximum color fidelity. Unlike narrowband or aggressive UHC filters that eliminate most star color, the L-Pro selectively blocks only the primary wavelengths of artificial light, preserving the natural color of broadband targets like galaxies and star clusters.

    Is the Optolong L-Pro filter suitable for visual use?

    Yes, the L-Pro is effective for both visual observation and astrophotography. Visually, it darkens the sky background, making it easier to detect faint deep-sky objects from suburban locations. The improved contrast helps reveal subtle details in galaxies and nebulae that would otherwise be lost to skyglow.

    How will the Optolong L-Pro filter affect my images of the Andromeda Galaxy (M31) from a suburban backyard?

    The Andromeda Galaxy is a perfect target for the L-Pro. The filter will significantly increase the contrast between M31's faint outer arms and the brightened suburban sky. Crucially, it will do so while preserving the natural blue and yellow hues of the galaxy's star populations, providing a much more detailed and aesthetically pleasing image than you could capture without a filter.

    Can I use the Optolong L-Pro to image emission nebulae like the Orion Nebula (M42)?

    Absolutely. The L-Pro allows high transmission of the key emission lines that make up the Orion Nebula, including Hydrogen-alpha and Oxygen-III. It will suppress local light pollution, increasing the contrast and revealing fainter details in the nebula's structure while retaining natural star colors in the Trapezium cluster and surrounding field.

    Does the Optolong L-Pro filter block infrared (IR) light?

    Yes, the L-Pro filter effectively blocks infrared wavelengths. This is a key feature for astrophotography, as it means you can use it as your primary luminance ("L") filter with a monochrome CCD or CMOS camera without needing a separate IR-cut filter, which simplifies your imaging train.

    Do I need a different Optolong L-Pro filter for my DSLR and my telescope?

    It depends on how you want to use it. The Optolong L-Pro is available in multiple formats to suit different setups:

    • 1.25" and 2" Mounted: These thread directly into standard telescope eyepieces or camera nosepieces.
    • Clip-in Filters: These are designed for specific DSLR and mirrorless camera bodies (Canon, Nikon, Sony) and fit inside the camera, allowing you to use any camera lens.
  • Spectrum 380-750nm
    Surface Quality 60/40 (Refer to MIL-O-13830)
    Available Options 1.25" Mounted, 2" Mounted, Clip for Canon EOS APS-C, Clip for Canon EOS Full Frame, Clip for Nikon Full Frame, Clip for Sony Full Frame, Clip for Canon EOS-R
    Primary Function Multi-Bandpass Light Pollution Suppression
    Coating Technology Ion-Assisted Multi-Layer Coatings

    • Optolong L-Pro Filter (in selected format)

      × 1

    • Protective Storage Case

      × 1

  • Optolong 3-Year Warranty