Quote Originally Posted by RalphLambrecht View Post
i hope the sun is also calibrated to sunny 16 ,oe,e are in...
The "Solar Constant" bears that name for a reason. The sun's energy output is quite uniform.

The f/16 correlation should be accurate at mid latitudes for subjects illuminated by direct sunlight
without intervening attenuation, like high clouds, haze, smog, etc, and without abnormally high
ground-level reflectivity (sand, water, etc)..

- Leigh