Quick answer

Yes, a CPL filter can significantly reduce windshield glare and reflections in your dash cam footage, especially in bright sunlight. However, it won't eliminate all glare, and it may not work well if your windshield has a tinting film. For 70mai dash cams like the A810/A810S, the dedicated CPL filter is a simple add-on that improves clarity and color saturation.

How a CPL Filter Actually Works

A circular polarizing (CPL) filter mounts over your dash cam lens and acts like a pair of polarized sunglasses. It selectively blocks light waves that reflect off flat surfaces like your windshield, reducing the bright haze and reflections that can obscure the road ahead. The result is clearer footage with more accurate colors, especially on sunny days.

What It Can and Can't Do

A CPL filter is most effective against horizontal glare from the windshield and intense sun. It also enhances color saturation, making footage look more vivid. But it won't fix poor lighting at night, fog, or rain. In low-light conditions, the filter may slightly reduce the amount of light reaching the sensor, so you may notice a dimmer image. That's a trade-off worth knowing if you do a lot of night driving.

The Tinting Film Caveat

Before buying, check if your front windshield has a tinting film. As noted in the product specs, tinting film can interfere with how a CPL filter works. The polarizing effect may be reduced or produce uneven results. If your windshield is tinted, a CPL filter may not deliver the glare reduction you expect. In that case, you might want to test it or skip the purchase.

Verdicts on Common CPL Filter Claims

  • Claim: CPL filter eliminates all windshield glare: Verdict: Mostly true in bright conditions. It significantly cuts horizontal reflections and haze, but it can't remove glare from rain, fog, or direct headlights at night. It also depends on your windshield tint. Expect major improvement in sunlight, but not a total fix in all scenarios.
  • Claim: CPL filter makes night footage worse: Verdict: Partially true. The filter reduces light entering the lens, so footage can appear dimmer. However, many dash cams compensate automatically. The trade-off is acceptable for most users who want better daytime clarity. If you drive mostly at night, you may want to test the filter or leave it off.
  • Claim: CPL filter is easy to install and remove: Verdict: True. 70mai CPL filters are designed to clip or twist onto compatible dash cams. You can attach or remove them in seconds without tools. This makes it easy to take it off at night if you prefer. Installation is simple, so you can experiment with and without the filter.

Compatible CPL Filters for 70mai Dash Cams

  • 70mai CPL Filter for Dash Cam A810/ A810S: The 70mai CPL2 is compatible with the Dash Cam A810/ A810S. It reduces surface reflections on your windshield or intense sun, making it easier to see the road ahead. It also enhances color saturation for more vivid and accurate colors in your footage. If you own an A810 or A810S, this is the exact filter you need. It clips on easily and immediately cuts glare, so your footage is more usable for evidence or just watching back.
  • 70mai CPL Filter for Dash Cam 4K Omni: The 70mai CPL Filter for Dash Cam 4K Omni reduces surface reflections and intense sun, enhances color saturation, and protects your lens from fingerprints, scratches, and dirt. For the 4K Omni model, this filter not only reduces glare but also adds lens protection, which is handy for a camera that rotates and is more exposed to dust and smudges.
  • 70mai CPL Filter for Dash Cam A410/ A510/ A800SE/ A500S/ Lite 2: The 70mai CPL Filter is compatible with the Dash Cam A510, A800S, A500S, and Lite 2. It reduces surface reflections and enhances color saturation. If you have one of these older or mid-range models, you can still get the same glare reduction benefit. It's a low-cost upgrade that improves daytime footage noticeably.