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Optolong L-eXtreme Filter – Best Light Pollution Filter for Astrophotography

The Optolong L-eXtreme Filter is one of the most advanced light pollution filters available, engineered to allow astrophotographers to capture high-contrast celestial images under light-polluted skies. With a focus on the H-alpha and OIII emission lines, this dual narrowband filter provides superior image clarity, even in urban environments. Whether you’re using a DSLR, CCD, or CMOS camera, the L-eXtreme filter enables you to capture detailed nebulae and other deep-sky objects with remarkable accuracy.

Key Features:

• Targets H-alpha (656.3nm) & OIII (495.9nm, 500.7nm) emission lines for enhanced nebula imaging.
• Eliminates 99.9% of light pollution, blocking major artificial light sources like mercury (Hg) and sodium (Na) vapor lamps.
• Achieves an impressive 93% transmission rate, ensuring high signal clarity and sharp contrast.
• Ideal for use with DSLRs, CCDs, and CMOS cameras for astrophotography enthusiasts of all skill levels.
• Suitable for capturing nebulae, galaxies, and star clusters under heavily light-polluted skies.

How the Optolong L-eXtreme Works:

This filter is designed to isolate the narrow emission lines of deep-sky nebulae, specifically H-alpha and OIII, while blocking out the majority of artificial light pollution. It's perfect for capturing emission nebulae such as the Orion Nebula (M42), the Horsehead Nebula (IC 434), and planetary nebulae like the Ring Nebula (M57). By targeting these specific wavelengths, the L-eXtreme filter ensures higher contrast and more detailed astrophotographs.

Technical Specifications:

The Optolong L-eXtreme Filter is optimized for deep-sky astrophotography, particularly for emission nebulae. Here’s what makes it special:

Major Emission Lines Targeted:

• H-alpha (656.3nm) – The red emission line emitted by hydrogen atoms, found in many nebulae.
• H-beta (486.1nm) – A complementary emission line emitted by hydrogen atoms, also targeted for nebula imaging.
• OIII (495.9nm, 500.7nm) – Emission lines from doubly ionized oxygen, often found in planetary and emission nebulae.

Artificial Light Pollution Blocked:

• Mercury (Hg) lines: 435.8nm, 546.1nm, 577nm, 578.1nm
• Sodium (Na) lines: 598nm, 589.6nm, 615.4nm, 616.1nm

Note: Optolong continuously optimizes the performance of this filter based on real-world testing, so technical data may be subject to updates.

Available Sizes:

The Optolong L-eXtreme Filter is available in the following sizes:

• 1.25” mounted
• 2” mounted

Other sizes will be listed as they become available.

Astrophotography Results:

Photographers around the world have achieved breathtaking images using the Optolong L-eXtreme Filter, even under severe light pollution conditions. Whether you're working with a DSLR camera or a more advanced CCD/CMOS setup, this filter helps you capture intricate details of nebulae and other deep-sky objects, making it a must-have for astrophotographers in urban environments.

Example Captures with the Optolong L-eXtreme:

• Object: M42 (Orion Nebula)
• Camera: ZWO ASI183MC Pro
• Telescope: Sky-Watcher N130/650 with coma corrector
• Mount: iOptron CEM25EC
• Guide: 120mm mini guide scope, ZWO ASI120MM mini
• Light Pollution: Level 7–8 (City center, high light pollution area)

Additional Example:

• Object: NGC6946, Barnard 150, and Sh2-129 Flying Bat Nebula
• Camera: Canon 6D (modified) + WO SpaceCat 51
• Filters: Optolong L-eXtreme & L-Pro
• Data: RGB 25 x 600" ISO 3200 (Optolong L-Pro) / H-Alpha & OIII 20 x 1500" ISO 3200 (Optolong L-eXtreme)

Package Details:

• High-quality silver cardboard box for storage
• Plastic PP box for added durability
• Imported high-pressure EVA case lining to protect your filter

Why Choose the Optolong L-eXtreme Filter?

Whether you’re an experienced astrophotographer or a hobbyist looking to take your images to the next level, the Optolong L-eXtreme Filter is a powerful tool that delivers incredible results. Its ability to cut through light pollution, combined with its high transmission rates, makes it a top choice for capturing nebulae, galaxies, and other deep-sky objects.

Get Yours Now!

The Optolong L-eXtreme Filter is available for immediate purchase in 1.25” mounted and 2” mounted sizes. Upgrade your astrophotography gear today and start capturing the cosmos in stunning detail, even from the heart of the city.