Quote Originally Posted by 2F/2F View Post
The dome needs to be pointed at the right thing, of course.
I'm uncertain whether this means "towards the camera" or "towards the sky" (in outdoor full sun)---I can see an argument for both. In this setting it didn't make too much difference; the sun was *extremely* bright ("sunny 22" conditions) and there was a lot of reflection from a light-colored landscape, so as long as I didn't throw an actual shadow on the dome I got pretty consistent readings in all directions.

And no; assuming the same value is used for middle gray with both meters, a gray card reading should not match an incident reading. You should have to open up 1/2 to 2/3 of a stop from a gray card reading to match an incident reading.
I don't understand this part. Isn't the idea that the dome looks to the meter like a gray card?