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Have a question? We'd love to help. Email: Call Us: (587) 336-6621 Toll Free: 1 (866) 310-8844

ZWO 1.25" Duo-Band Filter (ZWO-DB1.25)

by ZWO
Original price $102.70 - Original price $102.70
Original price
$102.70 - $102.70
Current price $102.70

Product is not in stock at the moment but we expect it to arrive soon.

New stock is arriving all the time. We will let you know an estimated timeline for when your reserved item will arrive.

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.


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 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.

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 and comes in both 1.25” and 2” sizes.


  • Aerometal material. Precise CNC machining
  • Fine sandblasting process and anodized finish
  • Extinction treatment to prevent reflection
  • Laser engraving font that will never fade
  • Precise double-sided optical coating
  • Fine-optically polished to ensure accurate 1/4 wavefront and <30 seconds parallelism over the both surfaces


  • Name: ZWO Duo-Band Filter
  • Size: Standard 1.25”
  • Glass thickness: 1.85 mm
  • Bandwidth: HA (15nm) OIII (35nm)
  • Surface quality: 60/40 (Refer to MIL-O-13830)
  • Schott substrate material
  • More than 90% transmission at major OIII line 495.9nm and 500.7nm.
  • More than 80% transmission at Ha line 656.3nm

Customer Reviews

Based on 1 review
SD LeFranc
Works like a charm

My first light with this dual band filter was under 90% moon and shooting M33 Triangulum Galaxy. While the filter is not made for galaxies, it did a better job of gathering data in comparison with my UHC and UV/IR cut under moonlit conditions. My second attempt was IC63 the Ghost of Cassiopeia. The result, under a 99.9% moon, sept 9, was exactly as it should be. I could barely see the main stars of Cassiopeia through the moonlight, but the dual band filter cut all that out and worked like a charm. I would like to see a direct comparison between the “L” filters though.
Thanks to the staff at All Star for their great service.