Astronomik H-alpha 6nm CCD MaxFR Clip-Filter EOS R XL

MaxFR Astronomik photographic narrowband-emission line filters for fast optical systems.

There is an ever-growing demand for filters suitable for extremely fast optical systems like Celestron's RASA and the Takahashi Epsilon Astrographs.

Our novel MaxFR emission line filters are suitable for very fast focal ratios. The Astronomik MaxFR series of narrowband-emission line filters is perfectly matched to the requirements of astronomical deep-sky imaging with fast optical systems. For the three most important emission lines—oxygen (OIII), hydrogen (H-alpha), and sulfur (SII)—you may select filters with either 12nm or 6nm bandwidth (FWHM).

Highest transmission:
Our new MaxFR filters are designed to work perfectly with fast optical systems. The MFR Coating technique provides the best out-of-band blocking possible across the range of wavelengths from UV to IR. The new design offers extremely high contrast, minimized stray light, no halos, and needle-sharp stars. Astronomik MFR narrowband-emission line filters provide the best data quality for producing stunning final images.

• 12nm MaxFR filters: Usable from f/1.7 to f/8, with about 85% maximum transmission at f/1.4 guaranteed.
• 6nm MaxFR filters: Usable from f/2.2 to f/8, with about 90% maximum transmission at f/2 guaranteed.

For maximum contrast, the SII filter is carefully designed to block all light from H-alpha and NII (nitrogen).

Imaging with Narrowband-Emission Line Filters
Narrowband-emission line filters are perfect for observing from light-polluted areas. H-alpha filters should be your first step into narrowband astrophotography, allowing deep, contrast-rich images even in severe light pollution or under a full moon. H-alpha filters are ideal for capturing red-glowing nebulae. OIII filters enable imaging of greenish-blue structures, such as planetary nebulae and star-forming regions. SII filters complete your HSO set, letting you process your images like those taken by the Hubble Space Telescope!

Quality aspects of the new Astronomik MFR narrowband-emission line filters:

• MFR Coating: Use 12nm filters on systems as fast as f/1.4, and 6nm filters as fast as f/2.
• High-Quality substrate: Made from stress- and striae-free, optically polished glass. The filters consist of ultra-thin layers on the substrate.
• Parfocal filters: All Astronomik filters are parfocal, with thickness tolerances that prevent the focal plane from shifting when changing filters.
• Coating: Coated on both sides with up to 170 layers for anti-reflection properties.
• Durability: Scratch-resistant, moisture-proof, and designed to last for years without degradation. Every Astronomik filter will deliver full performance and meet specifications even after years of use.
• Integrated Blocking: Complete blocking from UV to IR, eliminating the need for additional UV & IR blockers.
• Available Sizes: From 1.25" to 50mm x 50mm square filters.
• Delivered in a high-quality protection & storage box.
• 10-year guarantee thanks to our outstanding coating technique.

You’ll get the highest quality with every Astronomik filter, enhancing your imaging possibilities. These filters provide long-lasting performance, working as well as when they were brand new. With our special coating, the filters do not degrade over time, and the MFR coating ensures compatibility with nearly all optical systems.

Frequently Asked Questions:

• Which is the best FWHM for me – 12nm or 6nm?

It depends on your setup. For DSLR cameras and dark-current-limited cameras, 12nm filters are ideal. For extreme light pollution and cameras with low dark current, 6nm filters provide better contrast and star reduction, making them suitable for deep imaging.

• How does exposure time change with narrowband filters?

Using narrowband filters doesn’t necessarily require longer exposure times, but you can extend exposure to record fainter details without unwanted light interference. This results in clearer images, even from light-polluted areas.

MaxFR Filters for Fast Optical Systems
Choose the size and FWHM that fit your setup, and start capturing stunning deep-sky images today.