Fixing the dusk-to-dawn light

We have a light in our front yard that I have rigged with one of those dusk-to-dawn sensors. It has seemed lately that it's on almost all the time. I noticed the other day - when I put a green "Christmas" bulb in it - that there were a lot of cobwebs in it. So Tuesday I pulled it all out, and sure enough, the little sensor thing had a bunch of gunk inside it. I cleaned it out, and took my leaf blower to the inside of the light head, and when I put it back together it worked just like it used to. It's amazing how a little maintenance now and then can make a big difference in how things work.