Outside lenses get dirty, especially at this time of year but the second dash cam lens can be mounted inside the back window instead. The problem with most SUV's is that although the rear door glass looks big, the glass available for lens mounting with a good, undistorted view from the inside is much smaller.runrunshaw wrote: ↑August 20, 2018, 2:58 pm
I have an SUV. Not sure it would be very practical to put a stand alone cam on the rear door. With a dual cam, you can see both images on the screen in front of you at the same time and see the LED is on and it's recording. Without eyes in the back of my head, it would be a bit inconvenient to have to monitor the rear stand alone.
The second cam on dual units is always small, and generally, of a lower resolution (although there are some dash cams with both cams having the same resolution). Seems like twice as much trouble to have two units instead of one. Also, you'd need two SD cards, whereas the Rexing I bought only needs one. But if you have an extra camera lying around, then I guess, why not?
The second lens on a dual cam setup is low res but both video streams feed onto the same sd card on the one, front-mounted camera. The falling prices of high-speed/capacity sd cards made dual-lens dash cams cheaper and thus more common. The camera software writes the 2 separate video streams concurrently with a file for the front view and another file for the back view. Well that's how my current ~2300 baht one works.
I did have a Russian-made dual camera where the camera software formatted the sd card and also installed a bespoke video player on the sd card. If you placed the sd card in a computer, you only saw the executable and no video files. However, launch the inbuilt player and all the video files were there and the player was really quite good as it recorded g-forces on a rolling graph and mapped the gps info too. However, it was glitchy and after it irreparably screwed up a couple of sd cards, I ditched it.