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ZWO Hα 7 nm Filter - 31mm - Ha7nmD31

ZWO Hα 7 nm Filter - 31mm - Ha7nmD31 - Main image
$104.3 $149 In stock

Category: Telescope Accessories

ZWO 31mm H-Alpha 7 nm Filter

The Hydrogen-Alpha emission line is dominant among star-forming regions. Responsible for the red color in many nebulae, Hydrogen-Alpha (or H-Alpha) light is generated by hydrogen atoms is often the most popular narrowband emission line for astrophotographers to enhance in their images. Explore one of the main building blocks of our universe by imaging in Hydrogen-Alpha with a ZWO ASI camera, a filter wheel, and this narrowband filter!

The ZWO Ha 7nm 31mm Filter is unmounted. ZWO narrowband filters are fine-optically polished to reach an accuracy of 1/4 wave. Their performance is further enhanced by multiple layers of anti-reflection coatings.

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Customer Reviews (5.0 / 5 · 5 reviews)

William R. ★★★★★

Installed this 7nm Hα filter and the difference in contrast on the Orion Nebula was immediate—struggling stars almost vanished completely. It's surprisingly slim for a 31mm threaded ring, fitting tight into my filter wheel without any issues. First clear night I've had in weeks and the Ha detail cam

Matthew ★★★★★

Was worried about light pollution ruining my narrowband setup, but this 7nm Hα filter cuts through it beautifully—the star-forming regions in Orion popped with incredible contrast.

Ava J. ★★★★★

Shot two nebula targets on my first night out with this filter, and both came out noticeably cleaner — the 7nm bandwidth let me keep sub exposures long without drowning in sky glow. It threads in and out of the camera nosepiece smoothly, no tilt or backfocus headaches. Well worth the wait for the 31