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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
Optolong LRGB Filter Set

Optolong LRGB Filter Set

by Optolong
SKU OPT-LRGB-1.25
$249.00 - $359.00
$249.00
$249.00 - $359.00
$249.00
Price Match Policy!
  • Complete 4-filter LRGB set for monochrome cameras
  • High average transmission of over 90% for maximum signal
  • Blocks sodium light pollution at 589nm for improved color
  • Near-parfocal 1.85mm substrate thickness minimizes refocusing
  • λ/4 transmitted wavefront ensures no degradation of optical sharpness
3 in stock
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  • Description
  • FAQ
  • Specifications
  • Warranty

  • Optolong LRGB Filter Set

    The Optolong LRGB Filter Set is engineered for monochrome astrophotography, dividing the visual spectrum into four channels to build high-fidelity color images. With an average transmission over 90% and a precise 1.85mm substrate thickness, this set delivers maximum light-gathering efficiency while maintaining a near-parfocal focus across all four filters. The B270 glass substrate is polished to a λ/4 transmitted wavefront and 30s parallelism, ensuring your telescope's resolution is perfectly preserved.

    LRGB Imaging: 4 Filters for Full-Color Monochrome Astrophotography

    This set enables you to leverage the high sensitivity of a monochrome sensor to create images with superior detail and color fidelity compared to one-shot-color cameras. The Luminance (L) filter captures fine detail across the visible spectrum, while the Red, Green, and Blue filters isolate their respective color channels. This method requires more acquisition and processing time but gives you complete control over color balance and noise reduction in post-processing. The OIII emission lines are strategically passed by both the Blue and Green filters, allowing for natural color rendition of planetary nebulae and supernova remnants.

    WARNING: These filters are NOT for solar observation. Looking at the Sun with this product, even for a moment, will cause permanent and irreversible blindness.

    Over 90% Transmission with a 589nm Sodium Line Notch

    Each filter in the Optolong LRGB set features advanced multi-layer coatings that achieve an average transmission of over 90%, maximizing the signal reaching your sensor. A key design feature is a deliberate gap between the passbands of the Green and Red filters, which effectively blocks the primary sodium light pollution line at 589nm. This targeted rejection enhances contrast and creates a cleaner separation between color channels, resulting in more natural colors straight from the camera, especially from suburban skies.

    1.85mm Parfocal Design with λ/4 Wavefront Accuracy

    Built on a B270 glass substrate, all four filters share a tight thickness tolerance of 1.85mm, making them nearly parfocal. This minimizes the need to refocus when switching between filters, saving valuable imaging time and streamlining automated sequences. The optical surfaces are polished to a transmitted wavefront of λ/4 and a parallelism of 30 arcseconds, guaranteeing that the filters will not introduce aberrations or degrade the sharpness of your telescope's optics.

  • What is the main advantage of using the Optolong LRGB Filter Set?

    The primary advantage is leveraging a sensitive monochrome camera to produce images with higher resolution and better color control than typical one-shot-color cameras. By capturing separate Luminance, Red, Green, and Blue channels, you can optimize exposure for each, process them individually to reduce noise, and combine them for a final image with maximum detail and accurate color.

    Why is there a gap between the green and red filters in the Optolong set?

    This gap is a specific design choice to block artificial light pollution. It targets the prominent sodium vapor lamp emission line at 589nm. By blocking this wavelength, the Optolong LRGB filters reduce skyglow and improve the color balance and separation between the red and green channels for more natural-looking results.

    Are the Optolong LRGB filters parfocal?

    They are designed to be nearly parfocal. All filters in the set are made with a 1.85mm thick substrate, which minimizes the amount of focus shift required when changing from one filter to another. This is a significant benefit for automated imaging sessions, as it reduces the need for constant refocusing routines.

    How does the Optolong LRGB set perform on a galaxy like Andromeda (M31) from a suburban location?

    This set is well-suited for imaging galaxies from light-polluted areas. The Luminance filter will capture the faint outer arms and dust lanes with maximum detail, while the targeted blocking of sodium light pollution in the RGB filters helps increase contrast and improve color saturation. You can achieve a deep, detailed image of M31 with a more natural color balance than you could with an unfiltered camera.

    Can I use the Optolong LRGB filters for imaging Jupiter with a monochrome camera?

    Yes, this set is excellent for high-resolution planetary imaging. Using a monochrome camera with these filters allows you to capture extremely sharp detail in each color channel. The Red filter will emphasize features in Jupiter's belts, while the Blue filter can highlight details in the zones and the Great Red Spot. Combining the channels gives you a vibrant, detailed final image.

    Is it safe to use the Optolong LRGB filters for viewing the Sun?

    ABSOLUTELY NOT. These filters are designed for night-sky imaging and provide no protection from harmful solar radiation. Attempting to view or image the Sun with these filters will cause instant and permanent eye damage and will destroy your camera sensor. Only use certified solar filters designed specifically for observing the Sun.

  • Substrate Material B270
    Substrate Thickness 1.85mm
    Average Transmission T>90%
    Blocking Range 350-1050nm
    Light Pollution Blocking >99%
    Transmitted Wavefront λ/4 RMS
    Parallelism 30 arcseconds
    Surface Quality 60/40
    Available Sizes 1.25" Mounted, 36mm Round Unmounted, 2" Mounted
  • Optolong 3-Year Warranty