ZWO Duo-Band Narrowband Light Pollution Reduction Imaging Filter - 2"

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ZWO Duo-Band Filter is a dual narrowband filter primarily aimed at complementing ZWO's 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 Hα (656nm) and OIII (500nm) 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 nebulae using a OSC camera.
If you are looking for a solution to deep sky photography in light pollution area, then the ZWO Duo-Band Filter will be a great choice.
The Duo-Band filter can be used with all ASI cameras and EFW Electronic Filter Wheels and comes in 1.25” (sold separately) and 2” (this item) sizes. However, please note that this filter does not have a female 2" thread so you cannot stack additional filters on to this.
Features:
- 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
Specifications:
- Name: ZWO Duo-Band Filter
- Size: Standard 2"
- 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 486.nm1, 496nm and 501nm.
- More than 80% transmission at Ha line 656.3nm
Important Note:
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.

Manufacturer part number: ZWO-DB2
Product carries a two year manufacturer warranty.
Useful Resources
Other Information
- Country of Manufacture: China
ZWO Duo-Band Filter is a dual narrowband filter primarily aimed at complementing ZWO's 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 Hα (656nm) and OIII (500nm) 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 nebulae using a OSC camera.
If you are looking for a solution to deep sky photography in light pollution area, then the ZWO Duo-Band Filter will be a great choice.
The Duo-Band filter can be used with all ASI cameras and EFW Electronic Filter Wheels and comes in 1.25” (sold separately) and 2” (this item) sizes. However, please note that this filter does not have a female 2" thread so you cannot stack additional filters on to this.
Features:
- 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
Specifications:
- Name: ZWO Duo-Band Filter
- Size: Standard 2"
- 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 486.nm1, 496nm and 501nm.
- More than 80% transmission at Ha line 656.3nm
Important Note:
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.

Manufacturer part number: ZWO-DB2
Product carries a two year manufacturer warranty.
ZWO Duo-Band Filter is a dual narrowband filter primarily aimed at complementing ZWO's 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 Hα (656nm) and OIII (500nm) 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 nebulae using a OSC camera.
If you are looking for a solution to deep sky photography in light pollution area, then the ZWO Duo-Band Filter will be a great choice.
The Duo-Band filter can be used with all ASI cameras and EFW Electronic Filter Wheels and comes in 1.25” (sold separately) and 2” (this item) sizes. However, please note that this filter does not have a female 2" thread so you cannot stack additional filters on to this.
Features:
- 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
Specifications:
- Name: ZWO Duo-Band Filter
- Size: Standard 2"
- 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 486.nm1, 496nm and 501nm.
- More than 80% transmission at Ha line 656.3nm
Important Note:
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.

Manufacturer part number: ZWO-DB2
Product carries a two year manufacturer warranty.
Useful Resources
Other Information
- Country of Manufacture: China

ZWO Duo-Band Narrowband Light Pollution Reduction Imaging Filter - 2"

