Let's try a quantitative approach. Plexiglass (poly-methyl-metacrilate, pardon my chemical engineering studies
) has a transparency of 92%, pretty much independent from thickness. It filters only 8% of light. A good optical glass is almost equivalent.
I took a screenshot with open canopy, and tried to measure the RGB in close areas of sky, 1 is free blue sky without canopy, #2 is behind the windshield. I don't know how much glass is in the armored windshield, but let's look at the figures:
The perceived brightness through the windshield (formula
HERE) is 82% of the clear undisturbed sky. A reduction of 18%, against 8% of pure Perspex is way too much.
I will do the same exercise for the lateral areas of the canopy.
Cheers,
Insuber