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Optolong L-Pro 77mm Filter

Optolong L-Pro 77mm Filter

Regular price $258.00 USD
Regular price Sale price $258.00 USD
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Introducing the Optolong L-Pro 77mm Filter, your ultimate companion for enhancing the contrast of deep-sky objects and minimizing sky background interference in your astronomical observations and astrophotography endeavors.

Enhanced Deep-Sky Contrast

Immerse yourself in the beauty of the cosmos with our advanced filter designed to selectively transmit the lines of deep-sky objects while suppressing various sources of light pollution. Experience heightened contrast and clarity in your observations of galaxies, globular clusters, and reflection nebulae.

Reduced Sky Background Interference

Say goodbye to unwanted skyglow caused by atmospheric oxygen emissions. Our filter effectively reduces the sky background, allowing you to capture clearer and more detailed images even in light-polluted areas.

Multi-Bandpass Design

Unlike traditional light pollution filters, the Optolong L-Pro Filter features a multi-bandpass design that minimizes its impact on color rendition. This makes it ideal for photographing continuum sources such as galaxies and globular clusters without compromising color accuracy.

UV and IR Blocking

With a spectral range of 700 - 1100 nm, our filter not only enhances astronomical observations but also blocks UV and IR wavelengths for added protection and image quality.

High Optical Quality

Crafted from high-quality glass and featuring fine polishing and multiple plane-parallel coatings, our filter ensures precise optical performance with minimal wavefront distortion and exceptional parallelism.

Durability and Stability

Our filter is built to withstand the rigors of astrophotography, thanks to the Iro Source Assisted Coating technology which provides durability, scratch resistance, and stability in central wavelength, unaffected by temperature changes.

Strict Quality Testing

Each Optolong L-Pro Filter undergoes rigorous testing with spectrophotometers and laser interferometers to ensure optimal spectral performance and wavefront accuracy, guaranteeing a qualified product for your astronomical pursuits.

Packaging Details

The filter is packaged in a silver carton with a PP plastic box and imported high-pressure EVA sleeve liner, ensuring safe transport and storage.

Product Specification

  • Brand: Optolong
  • Model: L-Pro
  • Filter Diameter: 77mm
  • Filter Type: Broadband Filters
  • Material: Glass
  • Mount Material: Aluminium
  • Coating: Multiple (plane-parallel)
  • UV and IR Blocking Range: 700 - 1100 nm
  • Transmission: High transmission at passband
  • Color Rendition Impact: Minimal
  • Optical Quality: High
  • Surface Polishing: Fine polishing for double-sided precision and λ/4 wave, <30 seconds parallelism on both surfaces
  • Cleaning Method: Ultrasonic wave cleaning substrate with purified water; cleaning by 13 tanks of purified water to effectively remove impurities and dust
  • Coating Technology: Iro Source Assisted Coating for durability, scratch resistance, and stability in central wavelength, unaffected by temperature changes
  • Quality Testing: Each filter undergoes strict quality testing processes with spectrophotometers and laser interferometers to ensure qualified spectral performance and wavefront accuracy
  • Packaging Details: Silver carton, PP plastic box, imported high-pressure EVA sleeve liner
  • Dimensions: Not specified
  • Weight: Not specified
  • Compatibility: Suitable for lenses with a 77mm filter thread
  • Usage: Suitable for both visual observation and astrophotography
  • Application: Ideal for reducing light pollution and enhancing contrast in deep-sky objects
  • Warranty: Not specified
  • Manufacturer: Optolong Optics Co., LTD.


  • The product specifications provided are subject to change for continuous improvement.
  • Color rendition may vary slightly due to factors such as light and display settings.
  • The coating of the filter may exhibit color changes depending on light and movement.
  • Optolong Optics Co., LTD. is committed to providing excellent quality products and customer service to support the growth and interests of amateur astronomers worldwide.

Join Optolong Optics Co., LTD. in your journey towards astro image perfection. With over 20 years of experience in optical filter coating, we are dedicated to providing you with the highest quality products and unparalleled customer support. 

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