For those who drive professionally or want to protect themselves from insurance fraud or police corruption, a dash cam can be critical to ensuring that you are not falsely accused of wrongdoing. They can also record scenic drives or capture anomalous events. The ideal dash cam reliably records high-quality footage every time you drive and can be forgotten about until you need to pull a clip from it.
Video Quality
Assessing footage is something we've gotten very good at through reviewing drones, projectors, and security cameras. We spent a few days driving around with each camera to see how each one performed in a variety of lighting conditions. While evaluating the footage, our main standard for quality was to see how well license plate numbers could be read when driving during the day and at night. We took screenshots from videos to assess how legible license plates were for each camera.
Video Capture
A dash cam can have the best video quality in the world, but if it doesn't reliably capture significant events and then save the resulting footage from being deleted, it's completely worthless. Every camera that we tested automatically begins recording as soon as power is turned on, which ensures that you won't miss anything. Each camera also has a G-sensor to automatically record and lock the files of events that occur after an impact. Before choosing cameras to test we combed through reviews to make sure there was evidence that their G-sensors reliably detect significant driving events. Once we purchased the cameras we then tested their G-sensors by tapping on them to make sure they'd detect a quick jerk. All of the cameras we tested passed these minimum bars for entry.
Video capture scores were based on recording reliability, recording settings, and the inclusion of rear-facing cabin cameras. For the most part, every model that we tested was reliable for day-to-day use but some stood out for having extra features to ensure that you can capture exactly what you want. It was especially nice to be able to adjust video clip lengths if you plan to review footage frequently or want to ensure that the G-sensor function will lock a long segment.
Interface
Regardless of video quality and reliability, if your dash cam is difficult to use or has a confusing interface it won't do you much good. There is a wide variety in how usable dash cams are. Some of our tested models had indecipherable menus, while others were impressively intuitive. If you have to break out the user manual every time you want to change a setting, then a dash cam won't be very helpful or convenient. Most models have options to change recording loop times, video resolution, LCD display time, and audio recording. Our testers spent time adjusting every significant setting and managing footage with each camera's interface, then rated each based on how simple or difficult the experience ended up being.
Visual Footprint
If you only drive one vehicle, a dash cam is something that you will likely install once and forget about until you need to pull footage off of it. Dash cams are legal in most states, but some laws limit the area of your windshield that they can occupy. Our testers preferred low-profile models with adhesive mounts. Compared to cameras with removable suction cup mounts, these take up much less space and aren't as visible in day-to-day use. We rated each camera's visual footprint with a subjective evaluation of how visible each camera was from the driver's seat, and by tallying how many times we caught the camera in the corner of our eye while driving.