Calculating amount of sun

Hi!

I decided to actually do an audit and see how much sun each zone I have is getting. The answer: a LOT less than I thought! Although I do expect that to change as summer gets here. My issue is that I have a lot of walls and trees, so I am running into a situation where a zone may be in sunlight, except for the foot or so right at the base of the wall, which is in hard shade from the wall shadow. Or a zone will be in sunlight, and then dappled shade as the tree shadow sweeps over it, and then back to sun. So how do I count for that in the amount of sunlight? I.e., do two hours of half shade/half sun count as 1 hour of sun? Or is it only the full hours that count? I also plan on repeating this in June, September, and December, because I know that the sun angle has a huge impact on the amount of light getting into places in my yard.

Thanks!

"do two hours of half shade/half sun count as 1 hour of sun? "
If the whole area is in full shade half of the time, then yes.

But where it gets complicated is if some of the area is always in the sun, and some is always or sometimes in the shade.
Then you may have to decide if watering the whole zone as the part that is always in the sun is best, as overwatering the area in part shade may be less damaging than underwatering the part that is always in the sun.