
Generally, a dash is only responsible for recording the road conditions directly in front of the vehicle, while some dash cams also offer dual-channel recording for both front and rear views. However, whether it's a single-channel or dual-channel dash cam, neither can see nor record the interior of the vehicle. Below are detailed introductions to single-channel and dual-channel dash cams: Single-Channel Dash Cam: A single-channel dash cam only records the road conditions directly in front of the vehicle through the camera on the device itself. This type of dash cam has fewer components, is easy to install, and is more affordable and practical. Dual-Channel Dash Cam: A dual-channel dash cam adds a rear camera to the single-channel setup, enabling it to record both front and rear views. However, the rear camera's functionality is limited. This type of dash cam is more expensive, has more components, is complex to install, and has a higher failure rate. Additionally, if a dual-channel dash cam is used as a streaming rearview mirror, the significant distortion from the rear camera can mislead the driver, causing misjudgment of distances and posing certain safety risks.

My dashcam has been installed for several years, and the basic model indeed only captures the view in front of the car. However, I later saw a colleague's version with dual front and rear cameras—the rear lens can record the inside of the cabin. Once, when I hitched a ride with him, I even saw my own image, and even the screen was clearly visible. However, this internal recording feature needs to be manually activated, and privacy is the key concern. I usually turn it off when I have passengers in the car. Having video evidence while driving is important, but it's inappropriate if private conversations with friends in the car get recorded. It all comes down to personal preference and how one weighs the trade-offs.

It depends on the specific model of the dash and its installation angle. Regular dash cams typically face outward through the windshield, but I've seen rearview mirror models with 180-degree rotatable lenses that can capture both the driver and front passenger. Last time when dropping my kid off at school, I noticed she forgot to buckle up from the footage. However, be aware of local laws – where I live, passengers must be informed before recording. Some newer models even come with facial blur features specifically designed to address privacy concerns.

I tried using a suction cup to mount the dashcam on the rear windshield, facing forward. It could barely capture the rear seats inside the car, but the footage was severely distorted. For proper in-car monitoring, you need to buy the ride-hailing-specific model with two independent lenses. Last time, a friend who drives for Didi installed a small camera on the headrest of the seat, clearly recording both the driving route and passenger behavior. This provides great protection for taxi drivers, especially during night shifts—having evidence prevents disputes from turning into endless arguments.

Yes, it's possible, but requires specific equipment. Regular dash cams are primarily designed to record the road ahead, but some models that support connecting to a rear camera can capture footage of the rear. If installed near the C-pillar, they can cover the back seat. I once helped my neighbor set one up—he specifically added a wide-angle lens to monitor his child's safety in the back seat. For such modifications, storage space is crucial. Dual-channel recording consumes memory card capacity rapidly, so a high-speed card of 128GB or larger is typically necessary.

Just researched this issue. Relying solely on the front camera can only capture the corners near the steering wheel; for a full view, professional equipment is needed. I've seen high-end models equipped with four fisheye lenses that can even record the corners of the trunk. These are quite common in cargo transportation, especially for cold chain logistics where temperature changes need to be monitored throughout the journey. For ordinary household use, it's not really necessary unless you frequently transport valuable items. Another issue is the infrared night vision function—to capture clear footage inside the car, you'd need to choose a model with a fill light.


