On Tuesday, April 21, 2020 at 2:52:09 AM UTC-7, wrote:
On Tuesday, April 21, 2020 at 12:50:20 AM UTC-4, 2G wrote:
On Monday, April 20, 2020 at 2:26:27 AM UTC-7, wrote:
On Monday, April 20, 2020 at 5:49:26 AM UTC+2, Paul wrote:
Question: Is it possible to tint a canopy like a car, for example, using automotive window tinting material? I know some canopies are tinted a bluish color, but what about a dark black tint?

Thanks,

It's poorly advertised but Mecaplex offers an IR-blocking tint which I've ordered after some hassle.
As a fraction of light blocked:
Colour / Visible / IR
Standard grey / 76% / 74%
IR blocking grey / 77% / 47%
Blue / 78% / 78%

Sunlight is about 45/55 visible/IR(?), so my napkin math suggests assuming 1000W/sqm:

(450 * 0.76) + (550 * 0.74) = 749W
(450 * 0.77) + (550 * 0.47) = 605W
- ~25% cooler than typical tinted for no loss in visibility.

I don't know what fraction of either is blocked by an untinted canopy in comparison? Approximately 0% or more?

You don't need an IR blocking tint as acrylic blocks UV all by itself:

Some UV, not all. Acrylic blocks UV-B, so you don't get a sunburn. But it still lets significant UV-A through, which can cause deeper skin damage. Best to cover exposed areas with opaque material.

UV-A is defined as wavelengths between 315 and 400nm. As can be seen from the transmission plots I provided, acrylic falls off steeply at 400nm. This blocks almost, but not, all UV-A.

Tom