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

Collimatedbeam

The dual band pass nature of the Duo-Band filter passes light at Hα (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.

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.

Collimating lens

strange, like something in a dream or an imaginary world, especially in a way that is not based on practical, reasonable ideas

The incoming light transmitted through the filter should be perpendicular to the filter, or the incident angle should be less than 8°. Therefore, this product is not suitable for wide-angle or ultra wide-angle lenses.

Coherentlight

Laser collimation

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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.

Images captured with ASI color cameras and Duo-Band Filters. You can see that the potential for deep space photography in strong light polluted areas is vastly improved with the Duo-Band filters.