échelle de profondeur de champ
/eʃˈɛl də- pʁofɔ̃dˈœʁ də- ˈʃɑ̃/
n
English: depth-of-field scale · 景深标尺
Sens：Scale that shows the zone of sharpest focus around the subject; this is a function of the diaphragm’s opening and the distance between the lens and the subject.