Aperture
The iris in the lens that can be adjusted in size to control how much light enters through the lens. Aperture size is represented by f-numbers. Higher the f-number, smaller aperture size.
Shutter Speed
How long the shutter remains open. Slower the shutter speed, more light soaks up sensor.
ISO (International Standards Organization) Rating
Indicate light sensitivity of image sensor. Higher ISO number, greater light sensitivity and less light is required to expose the image.
Focal Length:
- Lens with focal length equivalency of less than 35mm = wide angle lens.
- Lens with focal length equivalency of less than 50mm produces the most natural view. The subject will be the same size/distance as you see it.
- A focal length up to 85mm = telephoto lens
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