ZWO 1.25" Duo-Band H-Alpha/OIII Filter

ZWO Duo-Band Filter is a dual narrowband filter primarily aimed at complementing our range of color ASI cameras. The Duo-Band filter is aimed at the astronomer who may already own a One Shot Color (OSC) camera and wants to image using narrowband techniques or emission objects without purchasing a mono camera, filter wheel and narrowband filter set.

The Duo-Band filter offers an economical entry into the world of narrowband imaging and can also offer a practical solution to imaging in light polluted urban areas.

The dual band pass nature of the Duo-Band filter passes light at H-Alpha (656.3nm) and OIII (500.7nm) wavelength, and can reduce the interference from natural light sources such as moonlight, or artificial light pollution such as street lighting.

It can help improve the contrast and visibility of deep sky objects such as emission nebula using a OSC camera. If you are looking for a solution to deep sky photography in light pollution area, then ZWO Duo-Band Filter will be a great choice. The Duo-Band filter can be used with all ASI cameras and EFW Electronic Filter Wheel.