So should HDR always be enabled on a Dash Cam??? How does HDR work exactly and will it affect image quality (for the worst)?
With the current HDR, some people like it, others don't, and it seems the results vary quite a bit between different people.
No dashcams so far seem to have got a good HDR working in all situations, and in any case it is never going to produce perfect results because of the way it works.
So try it and see if it works for you, if it does, use it, if it doesn't, that is unfortunate, simply turn it off again.
It does seem to be more use in dark conditions, especially if you have bright headlights and your plates use reflective backgrounds, which is why I said "probably worthwhile with winter approaching in the UK."
How does it work? well there are multiple designs that don't all work the same way, but basically every frame is a result of two exposures, a short one that has correct exposure for reflective number plates and a long one that has correct exposure for the shadows, the two frames are then combined by some algorithm that tries to use the short exposure for areas that where very bright and the long exposure for areas that were in the shadows, so the result should be good exposure everywhere across the image. It is not actually that easy though, and you get problems such as when plates are non-reflective they are not bright enough to trigger using the short exposure, and so they become unreadable due to the long exposure time used for that part of the image, which could be the problem Dashmellow is having, I don't think that description is very accurate for the A119 V3 HDR, but that is a good way to think about it, and some cameras use several exposures per frame.