cross post from, not MY POST...
Thermal Targets on the cheap - AR15.COM
Thermal Targets on the cheap - AR15.COM
Originally Posted By BushmanLA:
I figured this would be worth a thread since I keep seeing people talk about hand warmers and cold bottles of water.
You can by thermal targets and I'm sure they work great, but for those of us who want to save a little cash or need something in a pinch you have other options.
Just about any that seems reflective to normal light will probably also be reflective to thermal. The idea is that if you put a reflective target over a normal backdrop it will show up much cooler than the backdrop. I think this has to do with emmissivity or perhaps reflections of the cool sky or alien technology, but I'm not 100% sure so I'll leave it to the following pictures to convince you.
I've been using tinfoil taped to a plywood or cardboard box. For the sake of science I stopped at Wal-Marts and got a few other candidates.
I went home and did some arts and crafts with the kids and built up a black and white split backdrop of posterboard with a sample of each product on each color as well as one between the seam of the two colors. I brought it out into the sunlight and waited a few mins and got this.
Left to
Red Reflective Tape
DuckPrism Reflective Tape
Duckprism Sticky Sheet
Aluminum Foil Tape
A few notes. It only took about 30 seconds for the black side to get up to temp in the sun.
If you can't tell, the Aluminum Foil Tape works pretty flipping awesome. It is also the cheapest and most convenient to work with.
My kids liked the DuckPrism stuff, but it didn't work quite as well.
Red reflective tape soaked up too much sun and looked warmish but was still usable.
Edit: One other thing, you might notice the black side of the setup looks a little nonuniform, that is because it is actually hanging off the white foam board behind it by a few inches and this caused it to warm up in a non uniform manner. Pretty interesting how sensitive thermals are to seeing this kind of stuff.
Also, you will notice how much crisper the foil vs backround lines look in the ironbow mode. Color palettes are usually annoying when hunting but are great for sighting in rifles.
It is also pretty clear that you really could have used black construction paper on a white background, but that is a little bit of a hassle and requires both a white and black surface. The foil tape works pretty well on anything.
To show this I got a cardboard box and a piece of plywood. Both had been soaking up sun for a while so you can expect these kind of results all day long.
Plywood is on the left, cardboard box is on the right with a ingle strip of Aluminum Foil tape on either one. The original setup is in the middle with the same orientation. Image is in Blackhot polarity.
After a few hours of dark I'm going to go out and take a few pictures again. It works almost just as well in the dark if I can remember correctly.
Another pro tip. If you are using actual aluminum foil on a plywood backdrop, make sure you fold it up a few times or else the first shot that hits it will blow it to bits from all the wood splinters.
Also, all of this pics taken with an ATN TICO 640, which I should be doing a review of as soon as I can get my crap together.
