Wednesday, August 17, 2011

White Shirts are Cool



So I guess I have a lot of t-shirts. And now that I have a non-contact infrared thermometer a science/art project seemed to be in order. It's not strictly science because I didn't do a good job controlling how long I let these shirts come up to temperature before I took the measurement. You'll see there's a blue shirt towards the beginning that's cooler than the white ones. It might not have heated up all the way yet so I didn't count it as the minimum.

I had some problems with my equipment overheating. First the thermometer started to overheat. You can see in the pictures how extra LCD elements start showing through as I progress through the colors. Then it goes back normal. That's because I had to stop and wave it around in the shade until it cooled off. My original tripod setup put the LCD of my camera facing right into the sun. So when I stopped to cool off the thermometer the camera turned itself off and said ALERT! It's never done THAT before!

I moved the whole arrangement back to the edge of the little rectangle of shade cast by the building to get the camera in the shade and the shirts in the sun. Then both items overheated again anyway and I carried the whole arrangement into the air conditioning, let it cool off, then went back out and did the white shirts again. So it's not the best science, but it definitely shows a trend. Also the camera wasn't consistent with exposure. The blackest shirt doesn't look black when it's in front of the thermometer. In the previous picture when it's moving up the line you can tell it's a pitch black shirt. It was too hot and bright for me to adjust each exposure. I probably should have used automatic bracketing but I only just now thought of that.

This video doesn't meet my standards for perfection but it was just not really safe working conditions out there. The day after I shot these pictures I saw the high school football team practicing. Full blazing sun, scorchingly hot. They had a squad in dark red jerseys, one in dark blue jerseys, and one in white jerseys. The coach was walking around in a black shirt. I started to go over there with my thermometer and call the coach an idiot in front of everybody. But then I realized that this is Texas and they don't necessarily believe things like empirical evidence.

I guess evolution made some people more tolerant of heat. Maybe I'm extra sensitive. Hot things hurt me. I've asked other people if solder flux popping onto their fingers hurts them when they solder. They usually don't know what I'm talking about. The idea of my shoulders getting up to 145°F, five degrees from a medium-well steak, is just unacceptable to me. I wouldn't wear that black shirt of mine before dark. But the high school kids I see walking to their cars on my street at lunchtime in their black retro rock shirts seem to be totally oblivious to the fact that they are cooking. They have no hats, no sunglasses, and they're fine! Amazing.

1 comment:

  1. Good test. I remember pitifully little about heat and temperature from classes. I'm still surprised at how much of a variation there is in the test. I wouldn't have guessed at such a huge temperature difference between the white and black. Nicely done.

    Also, points to you for holding back on confronting the football coach. It might have made for a great video, but could have caused you to short out in frustration.

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