Comments by "nexus1g" (@nexus1g) on "Viofo A119V3 - The Best Budget Dash Cam in 2019" video.

Since the polarizing filter rejects some photons to increase image quality, it will inherently make night recording a little darker, though it too will be slightly clearer for the well-lit and bright areas. However, it's removable, so if it does make it too dark at night for your liking, you can remove it at night. Having a polarized filter is great for the day though, and worth it, if you ask me.
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@clarenceexd My pleasure! As far as I know, the aperture in the v3 fixed at f/1.6, so there's no increasing its light gathering. As far as exposure time, they have a seemingly arbitrary single-point 0.0 to 2.0 value, so that's not a huge help. I've no idea if this is post-processing to simply increase brightness or actual exposure time. Given it's called "exposure" in the manual, I'd suspect the latter, but there doesn't seem to be extra information gathered, just a brightening of what was already being gathered -- see the shadowed side of the houses that don't get any new detail as you might expect with actual longer exposure times. Moving objects also don't seem to blur more as the exposure value is increased leading me to believe more that it's post-processing. Though I'd have to test, I'd suspect that the actual exposure time is fixed to balance detail and motion sharpness while allowing for 60 FPS recording (so actual exposure time of course can't be slower than 1/60 if that's the case). If you look at the video 5:14, the v3 is definitely using the polarized filter based on the flare from the street lights and lack of reflection in the windscreen, and this segment slides through the gamut of exposure times from 0.0 to 2.0. This should give you a good idea from there how much detail you can glean at night through the CPL.
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