Figure 9 - Higher resolution photograph (704k) at 500ft of low beam headlight on-axis laser with passing-car

Distance 500ft (152 meters). Full moon night 1-25-2005. 1600 speed film. f/2 iris. Pentax MV1 ASA setting - stepped down to 1000 ASA. Pentax MV1 SLR 50mm lens with autoshutter timing. Angular width of image is approx. 35 degrees.

Comments: This image is identical in position to the 500ft low beam headlight on-axis laser view. The exposure timing is slightly darker, at 1000 ASA instead of 800 ASA, and understates the naked-eye glare. The camera is looking down the laser beam axis. A car is approximately 20 ft behind and 20 ft of the laser pointer and has its high beam lights on. The car is one lane over from the pointer, which is stationed in the road's shoulder. The car's high beam lights are oblique to the camera and understate the headlight glare seen if the car had passed in the lane adjacent to the pointer. The naked-eye view has more pointer glare, as shown in the previous 500ft image. The oncoming car's headlights are visible through the pointer glare and give an indication of their relative brightness.

Not captured photographically was a separate test on a rural road on January 23, 2005 at approximately 1300ft (396 meters). An oncoming car with high beams passed in the lane directly next to the pointer stationed on the road's shoulder. In that test, both the pointer's beam and the car's headlights were nearly aligned to optical axis of my eyes. At that distance and separation, high beam headlights and an on-axis Class IIIA laser pointer had a similar relative brightness.