Baader Premium H-alpha 7nm CCD Narrowband-Filter (2 Inch) (Pre-owned)

The Baader Premium H-alpha 7nm CCD Narrowband Filter is designed for deep-sky astrophotography, isolating the hydrogen-alpha emission line at 656.3nm to enhance the contrast and visibility of emission nebulae. Its narrow 7nm bandpass helps suppress light pollution and unwanted background light, allowing faint nebular details to stand out in astronomical images. Featuring precision-polished optical glass and dielectric anti-reflection coatings, this filter delivers high transmission while minimizing reflections, halos, and unwanted optical artifacts. The 2-inch mounted design is compatible with standard 2-inch filter threads and astrophotography accessories.

Condition: Excellent. No cosmetic or functional damage. 

Specs:

• Filter Size: 2 inches

• Central Wavelength: 656.3nm

• Bandwidth: 7nm

• Optical Thickness: 2mm (unmounted glass)

• Coatings: Dielectric anti-reflection coatings

• Optical Quality: Precision-polished, plane-parallel glass

• Mounting: Threaded 2-inch filter cell

• Primary Application: CCD and CMOS astrophotography

• Compatible Use: Deep-sky imaging with suitable telescopes and astronomical cameras

• Manufacturer Part Number: 2458384

Function:

This filter transmits light near the 656.3nm hydrogen-alpha emission line while blocking much of the surrounding spectrum, reducing the effects of light pollution and improving contrast in images of emission nebulae. It helps astrophotographers capture faint hydrogen-rich structures, including those found in the Orion Nebula and North America Nebula, even under less-than-ideal sky conditions. It is intended for astronomical imaging and is not safe for direct solar viewing or solar photography.