In this photo of Tom Platz squatting,…what can you observe?
-Foot Position?
-Angle of Shins?
-Angle of Torso?
-Chin/Head Position?
-His Breathing (Holding breath?)
The double lines on his sweats provide an excellent perspective.
Remember also, squat position varies for bodybuilding, powerlifting, Olympic lifting and strongman training. It also varies depending on body mechanics.