I am not sure how the physics of that works, however, but it certainly absorbs heat, even at low angles of incidence. (wattsupwiththat.com)
The canopy does not fold all the way out to protect from low angle sun exposure, but it covers enough to make early morning and evening stroll perfect. (strollerlab.net)
And isn't that just the point of low angle shooting? (karlascloset.com)