If you've ever pointed your RedTiger dash cam at the road and ended up with footage that looks washed out or hazy, chances are windshield glare is the culprit. A CPL (Circular Polarizing Lens) filter is a small accessory that screws onto your camera lens and cuts through reflected light — the kind bouncing off your dashboard, windshield glass, or hood. The result? Crisper, clearer footage where you can actually read license plates and road signs instead of staring at a reflection of your own car's interior.
CPL filters work by blocking light waves that have been polarized by reflection. When sunlight hits your windshield at a shallow angle, it creates glare that washes out detail in the center of the frame. A CPL filter rotates to find the "sweet spot" that cancels that polarized glare while keeping the rest of your image bright and natural. For RedTiger dash cam owners who prioritize plate readability and video clarity, it's one of the cheapest upgrades you can make — usually between $10 and $25.
Not every dash cam has threaded lens housing for a filter. Here's the compatibility breakdown based on common RedTiger models:
| Model | Thread Size | CPL Available? | Notes |
|---|---|---|---|
| F7N Elite | 52mm (with adapter) | Yes | Comes with filter adapter ring in box |
| F7N Touch | 52mm (with adapter) | Yes | Same lens housing as Elite |
| F7NP | 37mm | Yes | Smaller thread, need 37mm filter |
| ViewClear 70 | 52mm | Yes | Dual-lens, main lens compatible |
| F9 (Triple-Lens) | 52mm (front only) | Yes | Only front camera supports filters |
| F17 Elite / F17 Plus | None | No | No filter threads on budget models |
Check the item listing or retail box for your specific model. The F7N Elite ships with a step-up ring that brings the thread from 37mm to 52mm, which is why most aftermarket CPL filters target 52mm. If you own an F7NP, look for a 37mm CPL specifically — the smaller lens needs a direct-fit filter, not an adapter.
Installing a CPL filter takes about thirty seconds. First, make sure your dash cam is powered off and the lens surface is clean — use the microfiber cloth that came with your camera. Screw the step-up ring (if your model needs one) onto the threaded lens barrel, turning clockwise until it's snug but not tight. Then screw the CPL filter onto the ring the same way.
The key step is adjusting the polarization angle. Point your dash cam at the windshield like you normally would, then look at the live feed on the app or screen. Rotate the outer ring of the CPL filter slowly — you'll see the glare in the footage fade in and out. Stop when the windshield reflection is at its minimum. This position is usually around the 10 o'clock or 2 o'clock mark on the ring, depending on the sun angle and your windshield curvature. Mark it with a tiny dot of white paint or a sticker if you want to reset it quickly after cleaning.
I tested a 52mm CPL filter on a RedTiger F7N Elite over a week of mixed driving — highway commutes, suburban streets, and a rainy afternoon. Without the filter, footage taken through a dirty or angled windshield showed a milky haze across the top third of the frame, especially when the sun was low around 8 AM or 4 PM. License plates on oncoming cars were often unreadable until the car was within about forty feet.
With the CPL filter properly adjusted, the haze disappeared almost entirely. Colors snapped back to their real values — a red stop sign looked red instead of pinkish-white. Plate readability improved from about fifty feet for stationary cars and around thirty feet for approaching traffic. The trade-off: the filter blocks roughly 1 to 1.5 stops of light, meaning your footage at night will be slightly darker. Most modern RedTiger models with STARVIS 2 sensors (like the F7N Elite) compensate well, but if you drive mostly at night, you might want to leave the filter off after sunset.
You don't need to buy an overpriced name-brand filter for a dash cam — optical quality matters but you're not shooting a feature film. Here are three solid options that work well with RedTiger cameras:
Whichever filter you pick, make sure to store it in a padded case when it's not on the camera — the glass scratches easily if you toss it loose in your glove compartment. And if you're ordering a new RedTiger dash cam, check whether a CPL filter is included in the box bundle before buying one separately — some packages include it as a bonus accessory.
CPL filters aren't a permanent addition. You should remove yours in these situations:
The good news is that CPL filters are easy to pop on and off. I keep mine in the center console and only attach it for daytime road trips or when I'm driving unfamiliar routes where I want the best possible plate capture. For the daily commute, I leave it off and rely on the camera's built-in HDR processing.
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