Poor IR contrast in new Tennessee license plates

[33696933]

Only one new TN plate I've recorded up here in NY.

 

[wtimothyholman]

Only one new TN plate I've recorded up here in NY.

That's actually a pretty darned good image. Do you have some special lighting nearby? Perhaps a very bright streetlight, or exterior white lights?

 

[33696933]

Only one I've recorded up here in NY.
View attachment 135631

That's actually a pretty darned good image. Do you have some special lighting nearby? Perhaps a very bright streetlight, or exterior white lights?

Theres a streetlight about 50ft to the left but this area is pitch black. Taken with a 5442 Z4E with onboard IR set at 1/1000 shutter.

 

[richardgohth]

Only one I've recorded up here in NY.
View attachment 135631

Theres a streetlight about 50ft to the left but this area is pitch black. Taken with a 5442 Z4E with onboard IR set at 1/1000 shutter.

was the vehicle moving? distance of vehicle to camera?

 

[33696933]

was the vehicle moving? distance of vehicle to camera?

Yes moving ~45ft away

 

[wittaj]

I have noticed the closer we can get the camera to the plate, the better chance to read at night with these new plates. I temp rigged one about 30 feet away and the results were much better.

 

[wtimothyholman]

Yes moving ~45ft away

Your results make me wish that Dahua would market a -Z12 version of the 5442 series camera. The larger sensor and improved resolution makes a big difference in readability, even with the poor contrast of the new plates.

 

[wittaj]

The testing I mentioned in post #206 above with temp rig set up closer was with an older 5231R-ZE which is the same 1/2.8" sensor as the Z12E.

The ZE at 30 feet away captured the plate, but the Z12E at 175 feet did not.

Maybe a 5442 version of the Z12E would help, but I think we simply need to be closer to capture these new plates.

 

[Swampledge]

It appears to me that the reason that plate was so visible is that it is well lit by the vehicle’s (likely bright LED) license plate lights. If it had been an unlit front license plate, where IR illumination mattered, maybe not so good.

 

[wittaj]

It appears to me that the reason that plate was so visible is that it is well lit by the vehicle’s (likely bright LED) license plate lights. If it had been an unlit front license plate, where IR illumination mattered, maybe not so good.

Good point! I will see if I have any that came past that didn't have plate lights!

 

[33696933]

Yeah the 5442 is much brighter than the standard 2mp and unfortunately this car didnt have a front plate

 

[wtimothyholman]

Yeah the 5442 is much brighter than the standard 2mp and unfortunately this car didnt have a front plate

Tennessee vehicles only have rear plates. But the point about the LED plate lights is well taken. That's enough white light to account for the improved contrast.

 

[wtimothyholman]

The testing I mentioned in post #206 above with temp rig set up closer was with an older 5231R-ZE which is the same 1/2.8" sensor as the Z12E.

The ZE at 30 feet away captured the plate, but the Z12E at 175 feet did not.

Maybe a 5442 version of the Z12E would help, but I think we simply need to be closer to capture these new plates.

I think it would help quite a bit. If @33696933 is getting that type of image at 45 feet with a -Z4 camera, I certainly think I could do just as well at 80 feet with a -Z12 version.