MCQ
A camera objective has an aperture diameter $d.$ If the aperture is reduced to diameter $d/2,$ the exposure time under identical conditions of light should be made
- A$\sqrt 2 fold$
- B$2 fold$
- C$2\sqrt 2 fold$
- ✓$4 fold$
✓
Answer
Correct option: D.
$4 fold$
d
(d) Time of exposure $ \propto \frac{1}{{{{(Aperture)}^2}}}$
(d) Time of exposure $ \propto \frac{1}{{{{(Aperture)}^2}}}$
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