On Friday, March 25, 2016 at 12:00:00 PM UTC-4, Jeff Liebermann wrote:

Also, note that the color and surface finish of the dish is rather
important. The common gray color is designed to both reflect and
absorb a minimum amount of heat from the sun. If the dish were a
mirror finish, when the sun goes behind the satellite belt twice each
year, the reflected light would burn up the LNB. I've had it happen
on larger dishes. If the dish were painted flat black, it would

Hmm. OT maybe, but........ a little bit ago we needed to measure a large number of throws of Frisbee golf discs. I had one of those big reflective round traffic signs, about the size of a good size satellite disc. It was a No Entry One Way (but the international symbol, not words). That thing really reflects, my little LED headlamp will light it up two blocks away. The back of it is just gray sheet metal but the front, wow, that reflective paint is great stuff.

So the plan was have the kids throw from where the sign was set up, then go to where each disc lands and shoot back to the sign with my laser range finder.

Surprise. The range finder won't read off a reflective sign at all, at any distance. Turned the sign around and it read fine off the unpainted back. I hadn't expected that.