There are more iterations of dashcams out there, than sticks could be shook.
However, they're actually MOSTLY the same.
All are slight variations on a small list of Sensors and Cpus
Popular (good) Sensors:
-- Sony IMX 291 (2mpxl), 322 (2mpxl), 323 (2mpxl)
-- Ova 4689 (4mpxl)
Popular (good) CPU:
Ambarella, USA
-- A7, A12
Novatek, Taiwan
-- NT96650 and above
Ambarella is an old company, they know what they're doing. their latest cam cpu have fish-eye correction which is kinda nice.. but it's digital correction and some people get hung up on RAW-footage.
Novatek, when these guys first started they didn't even have a 1080p cpu, but over the years, they've caught up more than enough for _Dash Cam_ processing.
Sensors
All the sony sensors have better night vision.
The 291 has the highest sensitivity for night time, but in exchange, it has much worse day time color saturation, fidelity...
-- popular 291, viofo a119s
The 322, 323 are more/less equivalent. Night time on both is good, the 322 has higher gains, the 323 is more natural looking.
-- popular 322, 323, every other dash cam
The OV4689, this is the cheapest 4megapixel sensor on the market, so it's popular for 2560x1440 resolution cameras.
-- It has much better fidelity during the day due to the higher resolution, but it does not have the night time performance of the common sony cam sensors.
-- popular ov4689, a119(non-s), vantrue 2k, any cam advertising 2560x1440, or (pseudo4k), or 2880x2160 (interpolated),
Now..... Why are All Dash Cams Terrible:::
Main reason, Cost..
Manufacs have to make a profit.. the goal is to charge as much as possible.
The only way to infinitely increase profit is to increase the product's raw value. $600 phone, $800 phone, $1000 phone, $1200 phone, +++
HOWEVER, dash cam is in a unique category, where if it gets super expensive, heroin addicts will bust your windshield and steal the thing..
That is the hard limiter as to why ALL DASHCAMS SUCK..
@ ~$100, this is approximately the limit whereby it's not likely you will experience a break in.
This is the precise reason why all dash cams pick from a very narrow list of components.
The CPUs that fit into this bracket all have max bitrates of ~20-25mbit ~3Megabyte/second
The Sensors that fit into this bracket are all tiny and not very sensitive.
Recommendations:
If you're looking for a Dash Cam.. You should buy 3 per car.
1x with OV4689 for day time performance front
2x with Sony sensor for night performance front and back.
Do not get the Dual cam systems, because again, it runs off the same chip, if you split the 20mbit budget further, you only get the worst of both front and back..
The reason you don't need a higher resolution rear cam, is because if anything hits you from behind, it's going to be really close to you, so higher resolution isn't really necessary.
Never pay more than $100 per dashcam.
The more expensive iterations is identical in hardware to the cheaper ones.
They might have slightly better software and technical support, but again the difference is slight, and the only real support is warranty.
--- Now it's impossible to justify $200 for example the (Opia 2) when it performs identically as other cameras using the same internal hardware just for those reasons. Because you can buy 2x $100 cams, which would statistically last twice as long, regardless of warranty.
--- They're all nearly the same on the inside..
