Astronomik UHC Clip-Filter EOS XL – Ultra High Contrast for Deep-Sky Observation

The Astronomik UHC Clip-Filter offers exceptional contrast for deep-sky observation, providing more stars and details compared to other filters.

The Astronomik UHC (Ultra High Contrast) filter allows near 100% transmission of O-III and H-beta lines, while blocking unwanted light pollution, making gas nebulae and planetary nebulae appear in stunning detail. While not intended for visual use of the H-alpha line, it’s highly effective for electronic devices.

Main Use

The Astronomik UHC filter enhances deep-sky viewing, even for smaller telescopes starting at 2" (50mm) aperture. Its high transmission levels make it suitable for telescope focal lengths from f/4 to f/15, with no chromatic distortion or transmission loss at extremely fast focal ratios. Thanks to the high optical quality of the filter glass, you’ll notice needle-sharp stars, just like using your telescope without a filter.

Suitability

• Visual observation (dark skies): Excellent for telescopes of all apertures
• Visual observation (urban skies): Very good for telescopes from 100mm aperture
• Film photography: Good, but requires long exposure times
• CCD photography: Effective with an additional IR-block filter
• DSLR photography (original): Good with enhanced contrast but color balance shifted
• DSLR photography (astro modified): Excellent with near-perfect color balance
• Webcam / Video (Deep Sky): Good for combating light pollution

Technical Data

• 95% transmission at 486nm (H-beta)
• 95% transmission at 496nm and 501nm (OIII)
• 95% transmission at 656nm (H-alpha)
• Optimized for telescopes with focal ratios from f/10 to f/3.5
• Comprehensive blocking of unwanted wavelengths
• Ideal all-round deep sky filter, even for small telescopes
• Highly resistant to humidity, scratches, and aging
• Parfocal with other Astronomik filters
• Glass thickness: 1mm
• Delivered in a durable, high-quality filter box