Filter ZWO Duo-Band 1.25"

Filter ZWO Duo-Band 1.25

Product Description

The ZWO Duo-Band filter is a dual narrow-band filter intended primarily to complement the ZWO-ASI color camera range. The Duo-Band filter is intended for the astronomer who already owns a One Shot Colour (OSC) camera and wishes to image using narrow band techniques or emission objects without purchasing a mono camera, filter wheel and narrow band filter set.

The Duo-Band filter offers an economical entry into the world of narrow band imaging and also offers a practical solution for imaging in light polluted urban areas.

The dual bandpass nature of the Duo-Band filter allows both Hα (656nm) and OIII (500nm) wavelength light to pass through, and is able to reduce interference from natural light sources such as moonlight or artificial light pollution such as street lighting.

It helps to enhance the contrast and visibility of deep sky objects, such as emission nebulae, using an OSC color camera.

If you are looking for a solution for deep sky photography in areas with light pollution, then the ZWO Duo-Band filter will be an excellent choice.

The Duo-Band filter can be used with all ASI cameras and the EFW electronic filter wheel and comes in 1.25" and 2" sizes.

Technical Features

• Size: Standard 1.25
• Thickness: 1.85 mm
• Bandwidth: Hα: (15 nm); OIII (35 nm)
• Surface quality: 60/40 (refer to MIL-O-13830)
• Substrate material: Schott
• Over 90% transmission on mainline OIII 486.nm1, 496nm and 501nm.
• More than 80% transmission in the Hα line of 656.3 nm
• Filter cell material: aerometal. Precise CNC machining with fine sandblasting process and anodized finish
• Extinction treatment to prevent reflection
• Precise double-sided optical coating
• Optically polished to ensure 1/4 λ wavefront accuracy and 1/4 λ parallelism

Note: Incoming light transmitted through the filter must be quasi-perpendicular to the filter (incident angle must be less than 8°). Therefore, this product is not suitable for wide-angle or ultra wide-angle lenses.

Test results: The photographs shown in the image gallery have been captured with ASI color cameras and Duo-Band filters and show the potential for deep space photography in heavily light polluted areas and the enormous improvement with Duo-Band filters.

ZWO Duo-Band 1.25" filter