Astronomik H-alpha 6nm 1.25" CCD/CMOS Filter

Astronomik H-alpha 6nm 1.25" CCD/CMOS Filter

Description

The Astronomik H-alpha 6nm 1.25" is a narrowband filter tailored for astrophotography of emission nebulae in the H-alpha line at 656 nm. It is compatible with both CCD and modern CMOS sensors, making it an excellent tool for astrophotographers using monochrome imaging systems.

With a 6 nm full width at half maximum (FWHM), it efficiently blocks unwanted light from sodium and mercury vapor lamps, as well as skyglow. Its 96% peak transmission ensures high-contrast, sharp images, even from light-polluted urban locations.

The filter is equipped with Astronomik's MFR (Multi-Foil Reflection) coating and is optimized for optical systems as fast as f/4. It is mounted in a 1.25" threaded cell (M28.5), compatible with most filter wheels and accessories. Parfocal with other Astronomik filters.

Technical Specifications

• Filter type: Narrowband H-alpha

• Center wavelength: 656 nm

• FWHM: 6 nm

• Typical transmission: 96% at 656 nm

• Mount: 1.25" (M28.5) threaded cell

• Glass thickness: 1 mm

• MFR Coating: Yes, optimized up to f/4

• Parfocal: Yes (with Astronomik filters)

• Sensor compatibility: CCD and modern CMOS (monochrome)

• Recommended use: Astrophotography only

• Durability: Scratch, humidity, and aging resistant

Light transmission curve

Advantages

• High transmission at 656 nm for sharp contrast

• Compatible with CCD and modern CMOS sensors

• Excellent for urban or light-polluted skies

• Sturdy 1.25" threaded mount

• Parfocal with the entire Astronomik filter range

The Astronomik H-alpha 6nm 1.25" filter is ideal for astrophotographers looking to capture emission nebulae with outstanding clarity. Fully compatible with both CCD and modern CMOS sensors, it isolates the H-alpha emission line while blocking most sources of light pollution. It ensures superb contrast and signal quality, even with fast optics and in urban skies.