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
$4$ fold
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