Where to put the phone
Any angle you can film from is an angle Forge will measure, see the caveat for what each one costs. Square to the side, camera level with the bar, is the most accurate, because it is the only view where a lying athlete's own height can be used to set real-world scale. From the foot of the bench or behind the head, scale comes from shoulder breadth instead, which works from those angles and is looser.
What comes back
- Bar speed through the press
- Range of motion from chest to lockout
- Bar path deviation and tilt between the two arms
- Rep count and tempo
What is not reliable here
Bench is the only lift Forge tracks where the athlete is lying down, and that costs it a ruler. A lying body shows its true length only when it lies ACROSS the frame; filmed from the foot of the bench or behind the head it points at the lens, so height cannot be read and scale falls to shoulder breadth alone. Shoulder breadth is a population average against height and can be out by around a tenth on build alone, so distances, range of motion above all, are the numbers to treat with most suspicion from those angles. The set is still measured and still reported; it is a wider error bar, not a refusal.