Can I adjust exposure to be darker ?

[cam235]

Maybe a silly question here, but does the 4 MP box camera Dahua IPC-HF5421E (this one: http://www1.dahuasecurity.com/products/ipc-hf5421e-1004.html ) have an exposure bias setting in auto-exposure mode? I still want to have autoexposure, but I want to make the image overall darker than the default. Why? Because in late afternoon, when the background is in shade but the street is in direct sun, autoexposure gives me this type of image (front of car blown out to 100% white) and it would be more useful if it was a little bit darker.



In the MSIE plugin "Setup" control under Camera->Conditions->Exposure, Profile : Day, if I select Mode: Auto the only controls I see are Auto Iris (on/off) and 3D NR (on/off).
I would like something like Exposure Compensation: -10...0...+10

 

[nayr]

enable and crank up WDR; thats what you need.. the scene is too dynamic.. or mebe BLC

I dont run my LPR cameras at auto; they are fixed exposures.. daytime is very high and I'll still see that problem w/out WDR or BLC.

 

[cam235]

Thanks. I assumed any fixed exposure that worked for direct sun would end up too dark to be useful on a rainy day, but I'll give it a try.

 

[nayr]

not if you have an auto-iris lens.

 

[cam235]

Ah, that's how it works. Yes, I'm using a Theia DC auto-iris lens. I was thinking if I didn't choose auto-exposure then I would get fully manual settings with both the shutter speed and the aperture fixed.

EDIT: Using Shutter Priority mode, Shutter = 1/500, Auto Iris and a 40 mm lens, during the day I am seeing somewhat legible plates (by eye, not ALPR) out to 300 feet. I didn't expect that much range.