Technical tips for choosing the right dash cam for your car and why you really need it

Technical tips for choosing the right dash cam for your car and why you really need it
A car dash cam mounted on the front windshield recording the traffic ahead in case of an emergency situation or an accident

What they are, what they are for and why you should have one in your car. Safety, protection in the event of accidents but also the possibility of capturing unexpected panoramas and images: this is why it is an excellent idea to have a dashcam for cars on board.

I recently bought a new car and even before it was delivered to me by the dealer I was interested in choosing and buying a dashcam. This is an investment that, in the face of an average cost of no more than 200 dollars, protects both the driver while driving and the car itself, even when it is parked.
Let’s find out all the technical details together and evaluate which are the best dashcam models to choose.

A dashcam (or dash cam, abbreviation of dashboard camera or dashboard camera) is a small video camera that applied to the windshield of vehicles has the purpose of recording events that occur outside the car in the direction in which this device is facing. Modern dashcam systems involve the use of two separate cameras, one to be applied to the front windshield and one to the rear window of the car in order to simultaneously record what is happening both in front and on the back of the car.
To film the passenger compartment of the car, dash cams with a closer focus are used, formerly known as taxicam, so called because they were initially used mainly by taxi drivers to protect themselves from malicious passengers.

A recent intermediate solution is characterized by two cameras integrated in a single device to be applied on the front windshield. The first camera faces outwards, the second inwards with a wide shooting angle. This greatly reduces the blind spots allowing the real ones under control almost the entire perimeter of the car.

In fact, thanks to the 140 ° wide-angle lens, the inward-facing cam allows you to capture not only the passenger compartment but also what happens in the vicinity of the door windows and the rear window. A useful system therefore, not only while driving in the event of an accident but also to monitor the car when it is parked, so as to have a watchful eye in the event of rear-end collisions (including lateral ones) or any act of vandalism.

Wide angle framing, focal length and focus

Without going into the specifics of the various types of sensor and their specific dimensions, in this kind of device for greater clarity the degrees of competence of the lens are directly indicated. The larger the angle of the frame, the wider the scene will be.
As for the focus, this is typically set to infinity in order to obtain the sharpest images even in the distance.
They are also equipped with an electronic image stabilization system useful for attenuating vibrations when shooting on the move.

One of the main features that distinguishes a dashcam from a common video camera is its framing ability. As already mentioned above, wide angle lenses are used that allow a wider shooting angle and greater depth of field. This result is also achieved thanks to a very short focal length which, depending on the sensor used, can vary from 12mm to 35mm.

Different kits for different needs

In this regard, there are essentially 4 different types of solutions which involve the use of systems with one or more dashcam in turn with one or two different cameras.
The most basic is the single dashcam with front camera (Figure A), a useful solution to capture everything the pilot sees during his journey. Cheap and easy to assemble, however, they do not allow you to obtain complete surveillance of what is happening around the car.

A second system is equipped with two distinct dash cams, one to be positioned on the front windscreen and another to be positioned on the rear window (Figure B). In this case we will have both a front and rear view so as to protect ourselves even in case of rear-end collisions.

Then follows the single dashcam system with double camera (Figure C). Here the device is mounted only on the front windshield with the first camera framing the front view while the second frames the interior of the car and therefore what happens around its side windows and rear window. These models are very popular lately because with an affordable price they allow as to have a more complete viewing angle.

A final solution is that which involves the use of two dash cams: the first with two video cameras, one front and one rear for the interior, the second instead positioned on the rear window (Figure D). This is a total control system that truly minimizes blind corners. However, in this case the costs rise and also the assembly requires some extra effort due to the cables that will have to cross the inside of the car.

Image sensor, resolution and frames per second

The image sensor is a device that converts the light waves that reflect from the object into information that represents an image. The resolution of the images is mainly related to the number of pixels, or rather megapixels (million pixels) that the sensor is able to “impress”. The higher the actual number of megapixels available, the higher the shooting resolution which in practice translates into a more detailed image.
The main resolutions used are HD (1280x720p), Full HD (1920x1080p), Super HD (2304x1296p), 2K (2560x1440p) and 4K (3840 × 2160p).

The frames per second, on the other hand, indicate how many different frames are captured in one second of shooting. Common dash cams are capable of recording at around 30 FPS, which is more than enough for smooth frame playback. However, more advanced models can allow shooting with a higher number of frames such as 60 FPS or even 180 FPS. The high number of frames, in addition to increasing the quality of the video, allows for more defined slow motion reproductions. A very useful feature, for example, in the event of road accidents, where it is necessary to study the dynamics of the facts in slow motion and with precision.

HDR and WDR: brightness and color depth

HDR’s full name is High-Dynamic Range. Compared with ordinary images, it can provide a more dynamic and detailed color range of the image. Unlike LDR (Low-Dynamic Range) images with different exposure times, the final HDR image is finalized by superimposing different LDR images and yielding the best details obtained with different exposure times.

HDR and WDR (Wide-Dynamic Range) are two different processing technologies that allow a rather similar final result. The first is a hardware solution while the second uses software processing. The purpose of HDR and WDR is the same, which is to sharpen details in dark areas or in high contrast conditions.

If you take care of the dark details, the highlights will be overexposed. To solve this problem, we use HDR technology. Simply put, it’s a photo that contains both light and dark details.
However, HDR technology can only be used for still images, while WDR can also be used for video thanks to the support of the high-speed DSP processor (Digital Signal Processor).

Motion sensor and G-Sensor (shock)

The motion sensor is a tool that allows you to automatically start a recording as soon as the camera detects movement in front of the car, or if someone damages it even while it is off and parked. A feature that can help us identify potential thieves and troublemakers. The G-Sensor, on the other hand, intervenes in the event of an accident by saving the video of the event in an area protected from overwriting. In fact, when the memory card is full, the new file automatically overwrites the previous recording, except for the locked file. The sensitivity to shocks and jolts with which this sensor intervenes is often adjustable (Off, Low, Medium, High).

GPS and speedometer

Since these are video cameras intended primarily for use on the move, it is useful to make sure that the functions include GPS and the speedometer.
Their detected data will be printed directly on the video being recorded, so as to have a more precise and complete picture of the recorded route.

All clear, but which one to choose?

I have selected the best models to meet various needs for different price ranges.
The most expensive and top-of-the-range model may not always be the right solution for us. In addition to the quality of the saved images, the number of cameras included in the kit and the method of assembly inside the car must also be evaluated (usually very simple).
I therefore selected the best dashcam models to meet the various needs for different price ranges.
Let’s find out together.

Choosing a single front camera dashcam doesn’t necessarily mean opting for something entry level. With a high quality / price ratio we find the Garmin models such as the tiny and discreet Dash Cam Mini 2, little more than a key large, well hidden inside the car interior or, from the same company, the Dash Cam 67W, a model with extra-wide 180-degree field of view, 1440P HD resolution, 2 “LCD screen and voice control.

With an excellent discount, then we find the Rove R2-4K. It is a dash cam with a shooting angle of 150 ° and an excellent UHD 2160P sensor equipped with Super Night Vision Technology (Ultra-low liensor NT96660 + SONY IMX335) helps to get comparatively clearer footage and images from the recording in low light condition.

A leading company in the sector is definitely Vantrue, a brand that produces dash cams with components of the highest level and cutting-edge technical solutions. The form factor adopted by its top models is the one I prefer, with two cameras positioned on a single dashcam.
Among these we find the Vantrue N2S, a dashcam that has also obtained recognition from the main sector magazines such as Business Insider, CNET and Forbes.
The 4K front camera offers excellent sharpness and wide dynamic range, while the second camera records the inside with crisp, clear video at 1440P 30fps. The built-in GPS allows you to keep track of your driving path, position and speed, while the G-Sensor is able to detect any movement or collision that occurred when the car is parked. In addition, the advanced Sony sensor with updated WDR technology intelligently balances the exposure to provide clear and high quality video even in low light environments, in addition, the 4 infrared LEDs allow you to record flawless videos even when the interior it is dark.

Vantrue N2S 4K Uber Dual Dash Cam with GPS, 1440P Front and Cabin Car Dashboard Camera, 2 Channel Motion Detection Parking Mode Dashcam with IR Night Vision, Speed Record, Capacitor, Support 256GB Max
  • 【4K Single Front and 1440P Dual Dash Cam with Audio】The dual dash camera record a super QHD videos front and cabin simultaneously at 2.5K 2560x1440P with 30fps. Besides that, single front camera provides you with a crystal clear 4K video at 3840x2160@25fps. Capture any crucial evidence like license plates or road signs with ease. This dual car camera is your superior choice for Uber, Lyft, Taxi, Cab, and must-have for family road trip!
  • 【Trusted Witness for Accident】While the built-in G-sensor detects a crash, the video of the current accident will be locked and saved automatically into event folder to ensure important files are well protected. Supports class 10 or higher microSD cards up to 256GB(not included, need to buy separately). Recommend Vantrue or Samsung evo SD card.
  • 【Infrared Night Vision】The car camera adopts a Sony Starvis sensor, big aperture(F1.8 inside F1.4 Front),6 glasses lens and 4 IR LEDs, which provides a super Night Vision for capturing more important details when driving in the evening. The Infrared lights make it easy to record passengers clearly even at night.
  • 【24/7 Hours Parking Mode】Parking Mode triggered by the motion detection or collision detection. Motion detection enables the dual car camera to start record instantly when it detects movement in front or cabin of the vehicle; Collision detection enables the front and rear dash cam to auto power on and starts record if any crash is detected. Monitoring your car 24 hours a day for peace of mind.
  • 【Real Time Speed GPS Mount】The included external GPS suction cup mount allowing you to playback the video with the route, speed, and location on Google Maps via our Windows and Mac compatible GPS player, which make sure the speed evidence is protected when an accident occurs. You could also view the live speed in KM/H or MP/H on your dash cam during driving.

The Vantrue N4 is a three-way system with characteristics quite similar to the N2S. This however is equipped with a second dashcam with a third Full HD camera to be mounted on the rear window of the car.

Conclusions

The dash cam market now offers various solutions to meet the most particular needs and within the reach of all budgets.
As I have already said, my advice is to aim for a dual camera model mounted inside the same device so as to have a front video recording and what happens inside the car, which between the other allows to have, even if in a more limited way, also a view of what happens to the sides and back of the rear window.
Then the investment cost will also be proportional to the value you give to your car and to your safety in general.