EDIT: looks like this was my official 1,000th post here. How about that...
😎
Work has gotten very busy lately, but I did find some time to drive around in circles in traffic waiting for just the right opportunity to make some video captures using the new N5S camera. I have the N5S mounted side by side with the N4S which is fun because they both have 2.5k front facing cameras that use the very same sensor. Just for fun, I compared both of these to my Viofo A139 Pro camera, which is not entirely a fair comparison because it features a 4k front camera, but the results were a little surprising.
Here is the overall scene: I'm sitting in a turn lane with a red light and traffic is moving past in the lanes to my right at about 35-40mph. First up are images from each camera just to show overall renderings - these images are just screen captures from VLC player.
From the N5S: WDR mode is enabled, no adjustment to exposure. Circular polarizer is installed:
The same scene from the N4S is below. I need to re-adjust the exposure level to +0.6. When HDR and PlatePix are both enabled, the overall scene is a bit darker. It would be really great if these settings were stored in non-volatile memory in the camera so firmware updates don't blow away all of the setting changes that I make...
And finally, here is the same scene from my A139P (4k front camera) with HDR enabled:
The three images above are not precisely time-aligned because VLC doesn't allow the level of granular frame-by-frame advance that CapCut allows. So, using CapCut, I advanced the video from each camera, frame by frame, until the rear left wheel of the ambulance was aligned with the second white stripe from the crosswalk as shown below:
Then I zoomed in 250% and focused on just the license plate. Here are the results of a 250% zoom/crop on just the ambulance rear plate from each camera:
N5S:
N4S:
A139P:
As with the overall scene that I posted above, the N4S image is a bit darker, but both the N5S and the N4S render the plate in a manner that is completely readable. If I use photo software to adjust the brightness and contrast of the plate from the N4S, it very closely matches the image from the N5S. The surprise to me was the A139P that had the blurriest rendering of the three despite (or perhaps because of) its higher resolution.
Then, I advanced the video from each camera by 5 more frames (ambulance is now further away) to have another look.
N5S zoom/crop is still very readable
N4S zoom/crop starts to become more more difficult to read. In this case, merely increasing image brightness and contrast does not produce an image that equals that of the N5S. I've read a little about how Wide Dynamic Range is achieved through hardware and often produces a softer image than High Dynamic Range processing which is performed by software, but I have found exactly the opposite here. WDR from the N5S wins over the HDR + PlatePix from the N4S. I thought the lack of PlatePix in the N5S would be a detriment. This is not the case.
A139P: The rendering from the A139P is still readable and very similar to the lower resolution N5S camera and a pinch ahead of the N4S rendering. Again, this is a surprise given the higher resolution of the A139P.
I should probably repeat this set of images and zooms with HDR/WDR turned off and see how that impacts the clarity of the resulting images. That would be an interesting comparison and provide some additional insights about using HDR (or not) during the day with moving targets.
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