My son's 5th grade class picture was really sad. The lighting was one large umbrella about 10 feet up and bright as heck. The 8 or 9 kids with glasses all had glare except for my son, who has non-glare coating on his lenses because his mother is a photographer and hates the glare in the pictures. The only one without glare.
Do you generally let people leave their glasses on and angle their faces to not reflect, make them take off their glasses, or just don't care or do you work it out later in PP?
Have non-glare coating
