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Antlia H-Alpha 3nm Narrowband Filter - 2"
Antlia H-Alpha 3nm Narrowband Filter - 2" cuts out light pollution that enhances contrast for vibrant deep-sky astrophotography, even in bright skies.
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Capture stunning deep-sky images even under light-polluted skies with the Antlia H-Alpha 3nm PRO filter. This ultra-narrowband filter excels at boosting the contrast of emission nebulae and supernova remnants, delivering professional-grade results.
Here's why astrophotographers love it:
• Unmatched Contrast: The ultra-thin 3.0nm bandpass (only 1% of the visible spectrum) maximizes signal-to-noise ratio, resulting in exceptionally high contrast images with deep, dark backgrounds.
• Enhanced Suppression: Edge-blackening coating minimizes stray light and internal reflections, further darkening the sky and reducing star halos.
• Exceptional Transmission: With over 90% transmission at the key Hydrogen Alpha line (656.3nm) and only 0.1% transmission outside the band your images will come to life.
• Fast Optics Ready: Tested for use with systems as fast as f/3, including Hyperstar and RASA, with minimal signal loss, ensuring compatibility with your setup.
• Parfocal Design: Each filter is individually tested and guaranteed to meet strict tolerances, ensuring parfocality across your filter set.
• Convenience: Eliminates the need for an additional IR-cut filter by blocking both ultraviolet and infrared light.
Specifications:
| Passing band | 3 nm (FWHM) |
| Glass thickness | 2.0 mm ±0.05 (3.0 mm for 50 mm round & 50 x 50 mm square) |
| Optical flatness | 1/4 λ (wavefront) |
| Bandpass transmission | 90% |
| Off-band transmission | <0.1% (OD3) @ 300-1050 nm |
| Coating | Double-sided multilayer nano-coating |
| Surface quality | 60/40 (in accordance with US military watch MIL-O-13830) |
| Parallelism | 30" |
| Glass type | Schott monolithic optical substrate (non glued) |
| Filter sizes | Mounted 1.25", 2", Unmounted 31 mm, 36 mm, 50 mm round, 50 x 50 mm square |
Important Note: Never look directly at the sun through this filter, as it can cause severe eye damage.
Antlia: Experts in Astronomy Filters
Antlia Astronomy Filters are built by Deep-Sky Photography Enthusiasts for Enthusiasts all around the globe. Antlia prides itself on producing a series of exceptional quality, fully multicoated narrowband, dual-band, planetary and LRGB filters for astrophotography, designed for use with a range of monochrome and colour DSLR, CMOS and CCD cameras.
Product Code: ANT-Ha3nm2