ZWO 2" UV/IR Cut Filter

Product Overview

The ZWO 2" UV/IR Cut Filter is a full-size astronomy imaging filter designed to block ultraviolet and infrared light from reaching your camera sensor. It is useful with colour astronomy cameras that use an AR protect window rather than built-in UV/IR blocking glass.

Many astronomy camera sensors remain sensitive to infrared light. Since most telescope optics do not focus infrared at exactly the same point as visible light, unblocked IR can soften star profiles and reduce image sharpness. A UV/IR cut filter helps keep the recorded image focused on the visible spectrum.

Who Is This Product Best For?

This filter is best for astrophotographers using 2" filter drawers, filter wheels, adapters, or larger imaging trains where a 1.25" filter would be too small.

Why Choose This Product?

• 2" imaging format: Better suited to larger sensors and optical trains than a 1.25" filter.
• Visible-light sharpening: Blocks out-of-focus ultraviolet and infrared light that can soften images.
• M48 thread: ZWO lists the 2" version with an M48×0.75 male thread.
• Simple optical upgrade: Helps colour cameras produce cleaner visible-light images.

Recommended Uses

• Broadband colour astrophotography
• Lunar imaging
• Planetary imaging with colour cameras
• Visible-light telescope imaging
• 2" filter drawers, filter wheels, and M48-threaded imaging trains

Compatibility and Accessory Notes

This listing is for the 2" ZWO UV/IR Cut Filter. ZWO lists the 2" version with a 5mm body plus 2mm thread thickness and an M48×0.75 male thread. Choose this version when your imaging train requires 2" mounted filters or when using a larger sensor where a smaller 1.25" filter could vignette.

Important Limitations

• Not a narrowband filter: This is a UV/IR blocking filter, not an H-alpha, OIII, SII, dual-band, or light-pollution filter.
• Size matters: Use the 2" version only if your accessory train accepts 2" / M48-threaded mounted filters.
• Camera-dependent need: Some cameras already include UV/IR blocking glass, so check your camera window before stacking filters.

Frequently Asked Questions

What does this filter block?

It blocks ultraviolet and infrared light, allowing your camera to record primarily visible light.

Why use the 2" version instead of 1.25"?

The 2" version is better suited to larger sensors and imaging trains where a 1.25" filter may restrict the light path.

What thread does the 2" version use?

ZWO lists the 2" version with an M48×0.75 male thread.

Is this a light-pollution filter?

No. It is a UV/IR cut filter for visible-light imaging, not a light-pollution reduction filter.

Our Recommendation

Ontario Telescope recommends the ZWO 2" UV/IR Cut Filter for larger colour-camera imaging setups that need clean visible-light capture, reduced star bloat, and compatibility with 2" or M48-threaded imaging accessories.