Re: @Loyal Commenter
"The full field of vision subtends about 130 degrees horizontally"
Nope, that's more like the vertical field of vision, horizontally (unless you have tunnel vision) it is > 180 degrees.
"This fills my functional field of vision"
Well maybe that's what you should have said before, but I don't generally keep my eyes static (who does?) so my functional field of vision = my full field of vision.
