Thanks Michael and Premordial.
Michael, these were taken at f2.8. I just whacked it wide open to test it out and was surprised how good the results were. If I don't zoom right in they look good to me. The road is a dead end out to the dam wall and car park. The "headlight" was my torch that I switched on for a moment to pick up the barriers, but I was very pleased with the result. I particularly liked the way it fades to nothing, providing an element of intrigue. That's what I thought anyway!