# Thin-lens imaging
# Scope: Paraxial positive thin lens with real object beyond focus.
# Status: illustrative worked example; engineering review pending.
# Inputs are example values. Checks are editable example requirements, not standards.

focal = 50 mm
objectDistance = 300 mm

imageDistance := 1/(1/focal-1/objectDistance) [mm]
magnification := -imageDistance/objectDistance

check real image applicability: objectDistance > focal

scenario alternative: focal = 40 mm