How we worked it out
Updated as you change the numbers.
- 1/f = 1/d₀ + 1/dᵢ. Magnification = −dᵢ ÷ d₀.
Method and assumptions
Thin-lens approximation, using the real-is-positive sign convention.
Questions
Where does a 50 mm lens image an object 200 mm away?
66.67 mm behind the lens, at −0.333× (real, inverted).
Sources
Method and figures checked on . Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.