being a big SU fan I know from their famed horrid free throw shooting at the carrier dome it must drop about 10-15% at stripe. so probably 7% or so from the field. becuase the math from FT to FG is probably not congruent
the biggest problem is the depth perception. so maybe only 3-5% from field becuase the depth perception only changes when looking towards basket, not so much sides. thats why you notice it more at the charity stripe
I have never understood why its so much of a factor, hell I played 98% of my games out in the great outdoors,under the stars , in the wind, with poor lighting conditions.... now that is a real dome!
