WEST PALM BEACH, FL – A dashboard camera, commonly called a dash cam, is one of those automotive accessories many drivers do not think much about until something happens that they wish had been recorded. A collision at an intersection, a driver suddenly changing lanes, a hit-and-run in a parking lot or a disagreement over who had the green light can quickly turn into one person’s account of an incident against another’s. A dash camera can provide something considerably more useful: video of what actually happened.
Modern dash cameras have also become much more sophisticated than simple cameras pointed through the windshield. Depending on the system, a dash cam can record the front and rear of a vehicle, monitor a parked car, automatically preserve footage after an impact, record GPS information and transfer video directly to a smartphone. But those capabilities also make buying one more complicated. Resolution, image sensors, parking modes, memory cards, hardwiring, GPS, Wi-Fi, capacitors and other specifications can make two cameras that appear similar perform very differently. So, is a dash cam worth buying? For many drivers, the answer may be yes. Here is what you should understand before choosing one.
What Is a Dash Cam?
A dash cam is a compact video camera installed inside a vehicle, usually near the top of the windshield. Its primary purpose is to continuously record what is happening while the vehicle is being driven. Most cameras begin recording automatically when the vehicle is started and stop or enter another operating mode when the vehicle is turned off. Unlike a smartphone or conventional video camera, a dash cam is designed to operate continuously without requiring the driver to manually start a new recording every time storage becomes full. It accomplishes this through something called loop recording.
How Loop Recording Works
A dash camera typically saves video in a series of relatively short files rather than creating one enormous recording. When the memory card becomes full, the camera automatically begins overwriting the oldest ordinary recordings with new footage. In theory, the driver can therefore leave the camera running indefinitely without manually deleting old files. Important recordings can be protected from this process. If the camera detects a significant impact through its built-in G-sensor, for example, it can lock the corresponding recording so that normal loop recording does not immediately overwrite it. Most cameras also allow drivers to manually save a recording. This is one reason the size of the memory card matters. More storage generally means the camera can retain a longer history of ordinary driving before older footage is replaced.
The Biggest Reason to Own a Dash Cam: Evidence
There are plenty of entertaining dash cam videos on the Internet, but recording unusual events is not the primary reason most drivers should consider installing one. The most important benefit is documentation. After an accident, drivers may disagree about what occurred. Witnesses may have seen only part of an incident, and sometimes there are no independent witnesses at all. Video may show the position of the vehicles, traffic signals, lane changes, road conditions and the events immediately preceding a collision.
Dash cam footage may also be useful when dealing with an insurance claim. It does not automatically establish legal responsibility for an accident, but relevant footage can provide an insurer, police officer, attorney or court with additional evidence about what occurred. A camera may prove particularly valuable when the alternative is simply one driver’s version of events against another’s.
Front Camera or Front and Rear?
One of the first decisions a buyer faces is how many cameras the system should include. The least expensive configuration is generally a single forward-facing camera. It records the road through the windshield and may be perfectly adequate for someone primarily interested in documenting what happens ahead of the vehicle. A dual-channel system adds a second camera, normally mounted on the rear window. For many drivers, front-and-rear coverage is worth considering. A forward-facing camera might clearly record you stopping at a red light, for example, but a rear camera could provide a much better record of the vehicle that subsequently strikes you from behind. Some systems add a third camera pointed into the passenger compartment. These are particularly useful for rideshare, taxi and commercial drivers who want a record of activity inside the vehicle. For an ordinary private vehicle, a good front-and-rear system will probably provide the most useful balance of coverage and complexity.
Is 4K Really Better?
Resolution receives enormous attention in dash cam advertising. Common resolutions include 1080p Full HD, 1440p or 2K, and 2160p or 4K. All else being equal, higher resolution provides more image detail. That can become important when trying to identify a vehicle, road sign or license plate. The problem is that all else is rarely equal. A camera’s resolution tells you how many pixels are being recorded. It does not tell you how good those pixels will look. A poorly designed 4K camera can produce worse useful footage than a high-quality lower-resolution camera. Image sensor quality, lens quality, video bitrate, exposure, dynamic range, compression and image processing can all influence the final recording. Higher resolution also produces larger files, consuming memory-card capacity more quickly. Therefore, “4K” should be viewed as one specification rather than proof that a dash cam has excellent image quality.
License Plates Are Harder to Record Than You Might Think
Many buyers understandably assume that a high-resolution camera will clearly capture every license plate that passes the vehicle. Real-world conditions make that considerably more difficult. A license plate may be moving rapidly across the camera’s field of view. At night, headlights can illuminate reflective plate material while the surrounding scene remains dark. Rain, glare, windshield reflections, distance and differences in vehicle speed can further complicate the image. That means buyers should pay particular attention to actual sample footage, especially nighttime recordings and moving vehicles, rather than relying exclusively on a manufacturer’s resolution specification. A dash cam does not need to produce cinematic video. It needs to preserve useful information when something important happens.
The Image Sensor Matters
One specification worth investigating is the camera’s image sensor. The sensor is the component that converts incoming light into the digital image recorded by the camera. Better sensors can significantly improve performance in difficult lighting. This becomes particularly important at night, at dawn or dusk, inside parking garages and when moving between brightly illuminated and shadowed areas. A camera’s ability to manage high-contrast scenes can also affect whether details remain visible when headlights, streetlights or direct sunlight enter the image. When comparing cameras, buyers should therefore look beyond resolution and investigate sensor technology and real-world day and night footage.
Field of View: Wider Isn’t Always Better
Dash cameras commonly advertise wide fields of view, often somewhere around 120 to 160 degrees. A wider lens captures more of what is happening to the sides of the vehicle, which can be valuable at intersections. But there is a tradeoff. The wider the scene becomes, the fewer available pixels may be devoted to a particular object. An extremely wide field of view can also introduce distortion. The objective is not necessarily to purchase the camera advertising the widest possible angle. It is to capture enough of the roadway without sacrificing important detail.
What Is Parking Mode?
Parking mode is one of the most compelling reasons to purchase a more capable dash cam. Normally, a dash camera receives power while the vehicle is running. When the ignition is switched off, that power source may also turn off. Parking mode allows compatible cameras to continue protecting the vehicle after the driver walks away. Depending on the system, the camera may respond to movement near the vehicle, an impact, or both. Some cameras can also record continuously at a reduced frame rate while parked. Imagine returning to a parking lot and discovering a damaged bumper with no note left behind. A properly configured parking-mode camera might have recorded the vehicle responsible.
Buffered Parking Mode Is Particularly Useful
Not all parking modes work the same way. A basic system may begin saving video only after an impact or motion event has been detected. That can potentially mean missing the seconds immediately preceding the event. More sophisticated cameras offer buffered parking recording. The camera continuously maintains a temporary video buffer. When an event occurs, it saves footage from immediately before the trigger as well as what happened afterward. Those preceding seconds can provide valuable context. If parking surveillance is an important reason for purchasing a dash cam, buffered recording is a feature worth seeking.
How Does a Dash Cam Keep Recording When the Car Is Off?
Parking surveillance creates an obvious problem: the camera still needs electricity. One solution is hardwiring. Instead of simply plugging the dash cam into a vehicle’s USB or 12-volt outlet, a compatible hardwire kit connects the camera to the vehicle’s electrical system. A typical installation uses both a circuit that is active with the ignition and a constant-power circuit. This allows the camera to recognize when the vehicle has been switched off and enter parking mode. A properly designed hardwire kit should also provide low-voltage battery protection. If the vehicle battery falls below a selected voltage, power to the camera is shut off to reduce the possibility of leaving the driver with a vehicle that will not start. Dedicated external dash-cam battery systems are another option for drivers who want extensive parking surveillance without relying as heavily on the vehicle’s starter battery.
Will a Dash Cam Drain the Car Battery?
A dash cam operating only while the vehicle is running generally presents little concern. Parking mode is different because the camera is consuming power with the engine off. That is why low-voltage cutoff protection is important in a hardwired installation. Drivers who park for extended periods, drive infrequently or have an aging vehicle battery should be particularly conscious of power consumption. The correct installation can be just as important as choosing the camera itself.
What Is a G-Sensor?
Most modern dash cams contain an accelerometer commonly described as a G-sensor. It detects sudden changes in acceleration, such as a hard impact. When the threshold is exceeded, the camera can automatically protect the corresponding recording from normal loop deletion. Sensitivity matters. If the setting is too sensitive, potholes and hard braking may generate large numbers of protected files. If it is not sensitive enough, a minor collision might not trigger automatic protection. Fortunately, many cameras allow sensitivity to be adjusted.
GPS Is More Useful Than It Sounds
Built-in or optional GPS allows a dash camera to associate location information with recordings. Depending on the system and software, GPS can provide the vehicle’s route, position, time and speed. This information can add context to footage, particularly after an accident. Some drivers may prefer not to display speed directly on the recorded video, however, so it is worth checking whether the camera allows individual data overlays to be disabled.
Wi-Fi Does Not Usually Mean Internet Access
“Wi-Fi” on a dash camera can be misleading. In many cameras, Wi-Fi simply means that the camera can create a local wireless connection with a smartphone. The driver opens the manufacturer’s app, connects to the camera and can view or download recordings without physically removing the memory card. That is extremely convenient after an incident because footage can potentially be reviewed or saved immediately. It does not necessarily mean that the camera is continuously connected to the Internet.
Cloud-Connected Dash Cams
More advanced systems can provide genuine Internet connectivity, usually through a cellular connection or connection to an external hotspot. Depending on the product and subscription, cloud features may include remote notifications, vehicle location, remote viewing or automatic uploading of certain events. These capabilities can be attractive for vehicle security, fleets or parents monitoring a vehicle, but they introduce additional costs and complexity. A driver primarily interested in recording accidents may have little need for a monthly cloud subscription.
Don’t Ignore the Memory Card
The microSD card may be one of the least exciting components in the system, but it is extremely important. Dash cams continuously write, erase and rewrite video. That workload can be much more demanding than occasionally storing photographs on a conventional memory card. For that reason, a high-endurance microSD card designed for continuous video recording is generally preferable. Card capacity also matters. Higher-resolution cameras and multi-camera systems generate substantially more data. Before purchasing a card, check the dash cam manufacturer’s maximum supported capacity and recommended speed and endurance specifications. It is also wise to periodically verify that the camera is actually recording. A dash cam is of little value if a failed memory card went unnoticed for months.
Battery or Supercapacitor?
Dash cameras need a small amount of reserve power so they can properly save files when external power disappears. Some use rechargeable lithium batteries. Others use supercapacitors. For vehicles exposed to extreme heat, a supercapacitor-based design can be particularly attractive. Supercapacitors are commonly used in dash cams because they can tolerate demanding temperature conditions and do not rely on the same type of rechargeable lithium battery found in many portable electronics. That consideration becomes especially relevant in hot climates where the interior of a parked vehicle can become extremely hot. The supercapacitor generally is not intended to operate the camera for hours by itself. Its purpose is primarily to provide enough temporary power for an orderly shutdown and file preservation.
Heat Resistance Should Matter to Buyers
A dash cam spends much of its life directly behind a windshield. That is a harsh environment. Drivers in hot climates should pay close attention to the manufacturer’s stated operating and storage temperature ranges. Heat tolerance, mounting quality and the camera’s internal power design can matter just as much as flashy software features. A camera that performs beautifully on a test bench is not particularly useful if it cannot tolerate years of exposure inside a hot vehicle.
What About Night Vision?
Manufacturers frequently advertise “night vision,” but buyers should interpret the term carefully. A forward-facing dash camera does not normally illuminate the road with its own light. It relies on headlights, streetlights and available ambient light. What manufacturers generally mean is that the camera’s sensor and processing have been optimized for low-light recording. Infrared illumination can be useful for cameras recording the vehicle’s interior, especially for rideshare drivers, but infrared LEDs pointing through a windshield are not a substitute for good low-light road performance. Again, actual nighttime sample recordings are more valuable than marketing terminology.
A Polarizing Filter Can Reduce Glare
Some dash cams support a circular polarizing lens filter, commonly called a CPL. Its purpose is similar to a polarizing filter used in photography. It can reduce reflections and glare, including reflections from the dashboard that appear on the windshield. That can improve image clarity under certain conditions. However, a filter also reduces some of the light reaching the sensor, so its effects can differ between daytime and nighttime driving.
Screens Versus Screenless Cameras
Some dash cameras include a built-in display while others rely almost entirely on a smartphone app. A screen makes initial positioning, changing settings and reviewing footage convenient. A screenless design can be smaller and less distracting. Neither approach is inherently superior. What matters more is whether the camera can be installed discreetly and operated easily enough that the owner will actually maintain and check it.
Where Should a Dash Cam Be Mounted?
A dash camera should have an unobstructed view of the road while interfering as little as possible with the driver’s view. A common location is high on the windshield near or behind the rearview mirror. Drivers should also make sure the camera does not interfere with vehicle sensors, forward-facing safety cameras or other equipment housed around the mirror area. Windshield mounting laws vary by jurisdiction, so drivers should check applicable state and local requirements before installation.
Be Careful With Audio Recording
Many dash cameras include microphones and can record conversations inside the vehicle. That introduces legal and privacy considerations that do not necessarily apply to video of a public roadway. Audio-recording and consent laws vary by state and circumstance. Anyone who regularly carries passengers, employees, customers or rideshare passengers should understand the laws that apply where the vehicle is being operated. Most cameras allow audio recording to be disabled.
Dash Cam Footage Doesn’t Automatically Prove You Were Right
Drivers should remember that a camera records evidence, not necessarily evidence favorable to its owner. Footage could show that another driver caused a collision. It could also show that the dash cam owner was speeding, following too closely, failed to stop or otherwise contributed to the incident. GPS data, audio and video can potentially provide considerably more information than the owner initially intended to document. The purpose of the camera should therefore be an accurate record of events, not an assumption that every recording will support the driver’s position.
What Features Should You Actually Look For?
For most private vehicle owners, an excellent general-purpose dash cam would include:
- High-quality front recording, preferably 2K or 4K
- Strong real-world nighttime performance
- A quality modern image sensor
- Front-and-rear recording
- Reliable loop recording
- Automatic event protection through a G-sensor
- Buffered parking mode
- A compatible hardwire kit with low-voltage protection
- GPS
- Smartphone Wi-Fi connectivity
- Support for a large high-endurance microSD card
- A supercapacitor rather than a conventional internal battery, particularly in hot climates
- A discreet mounting system
- Good manufacturer support and regularly maintained software or firmware
Features such as cloud connectivity, LTE service, interior cameras and remote vehicle monitoring are useful for some drivers but should not necessarily be considered requirements for everyone.
How Much Should You Spend?
Dash cams range from inexpensive basic cameras to sophisticated multi-camera systems costing several hundred dollars before installation. Price alone is a poor way to judge them. A driver who simply wants a record of the road ahead may be satisfied with a relatively inexpensive single-channel camera. Someone purchasing a camera primarily for accident documentation and parking protection should probably spend more for dependable front-and-rear recording, better nighttime performance and a proper hardwired parking system. The important comparison is not how many features appear on the box. It is how well the camera performs the handful of jobs that matter when an incident actually occurs.
Is Professional Installation Necessary?
Not always. A basic dash cam can often be installed by mounting the camera and routing a power cable to a USB or 12-volt outlet. Rear cameras require additional cable routing, and hardwired parking installations are more involved. Modern vehicles can contain airbags, cameras, radar systems, complex electronics and trim panels containing wiring. Cables should never be routed in a manner that interferes with an airbag’s deployment. Anyone uncomfortable identifying appropriate fuse circuits or routing wiring safely may be better served by professional installation.
What Should You Do After an Accident?
If a significant event occurs, do not simply assume the recording will remain on the memory card indefinitely. Protect or save the relevant file as soon as it is safe to do so. If possible, copy the original recording to another device without modifying it and retain the original file. Depending on the circumstances, footage may be useful to an insurer, police officer or attorney. Do not unnecessarily edit the only copy of important footage.
The Most Important Dash Cam Feature Is Reliability
It is easy to become consumed by specifications. 4K. HDR. Wi-Fi. GPS. Voice control. Artificial intelligence. Cloud storage. But none of those features matters if the camera was not recording when something happened. A good dash cam should start reliably, continue recording without constant attention, tolerate the environment inside the vehicle and alert its owner when something is wrong. Owners should periodically check the camera, verify the date and time, inspect saved footage and make sure the memory card remains healthy. A five-minute check every few months could prevent discovering after an accident that the camera stopped recording long ago.
So, Should You Buy a Dash Cam?
For many drivers, a dash cam is a relatively small investment protecting a considerably larger one. Cars have become more expensive, repairs have become more expensive and determining exactly what happened during an accident is not always straightforward. A dash camera cannot prevent someone from running a red light, hitting a parked vehicle or disputing your account of an accident. What it can do is create an independent visual record.
For someone purchasing a dash cam today, the best overall setup will often be a discreet front-and-rear system with excellent day and night image quality, a high-endurance memory card and properly installed buffered parking mode with battery protection. You may drive for years without ever needing the footage. But if the day comes when two completely different stories are being told about the same accident, having a camera that recorded what actually happened could make the relatively modest cost of installing one seem insignificant.
Joe Mcdermott is a staff reporter who keeps his eyes peeled for interesting automotive news. He works mainly for our digital visibility company, SEARCHEN NETWORKS®. Mcdermott, one of our first and thus veteran reporters, is also a data analyst for select independent news and media organizations in the United States.