WDR vs BLC [PICS inside]

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n3wb
Jun 12, 2014
5
1
At night, I get better images/videos by using either BLC or WDR 20. Both images look pretty much identical to my eyes. Is there a benefit in using BLC vs WDR if the visual results are the same? Does BLC increase the noise like WDR?

I've included some pictures.
 

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Based on what it does to the bright wall next to the camera, I think the WDR option may be a little better than BLC. BLC washes out the wall a tiny bit more. Of course that could change for better or worse if you move the WDR strength around. Beyond that, I'm not sure of the difference between WDR and BLC.
 
WDR is usually better when there's likely to be a lot of variation in the lighting across the field of view, as it takes the entire image into account when it does the corrections.

BLC uses a smaller area for exposure control, so changes outside that area won't affect it. Typically, BLC is used where you need good exposure in one area, like a door coming into a shop with sunlight coming in the windows around the door. It'll expose for the door, and ignore the other areas. If you wanted to expose the dark top area and ignore the bottom area, BLC would do that.

Hik's BLC isn't great, as it just gives you a general area description and doesn't show what area it's using (at least on the version I'm using). Most cams let you draw a box around the area you want to use BLC on.
 
Based on what it does to the bright wall next to the camera, I think the WDR option may be a little better than BLC. BLC washes out the wall a tiny bit more. Of course that could change for better or worse if you move the WDR strength around. Beyond that, I'm not sure of the difference between WDR and BLC.

Max! Welcome! What took you so long to get here?! :)
 
Lol! Thanks! I've been swamped, and have been reading but not posting. This is where all the action is these days, it seems!

Would BLC result in less noise than WDR?

Yes, BLC doesn't really increase noise any more than the baseline exposure does; it just applies it to a smaller area. WDR will be noisier.

I'd recommend going out an walking the areas you care about at night with both settings. Stop, wave, turn around, and see if there's a big difference. In theory, WDR will give better exposure around the edges, but the WDR on these inexpensive cameras isn't great at night, as we've seen.