Question 1

What is the exposure triangle?

Accepted Answer

The exposure triangle balances aperture (f-stop), shutter speed, and ISO. Opening aperture 1 stop doubles light; halving shutter speed doubles light; doubling ISO doubles sensitivity. All three must balance for proper exposure.

Question 2

How do I calculate proper exposure?

Accepted Answer

Use the sunny 16 rule as baseline: at ISO 100, f/16, use 1/100s shutter in bright sun. Each stop brighter/darker, adjust one variable by one stop. Modern cameras use built-in light meters for accuracy.

Question 3

What's the difference between lumens and lux?

Accepted Answer

Lumens measure total light output from a source. Lux measures light arriving at a surface. Same lumens in a smaller area = higher lux.

Question 4

How do I convert old wattage to lumens?

Accepted Answer

Roughly: 40W incandescent ≈ 450 lumens, 60W ≈ 800 lumens, 100W ≈ 1600 lumens. LED equivalents use 80-90% less power for same lumens.

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