This video is part of our intro to photography series, where we break some fundamental concepts of the process of making image. You can find a written version below.
Introduction to exposure
What is exposure?
Exposure is probably the most important concept in photography. The word ‘photography’ is derived from the words “drawing with light”, so it is absolutely fundamental to the process when exposed to the amount of your camera.
What does the exposure define?
Three factors define how light your camera sees, and they are not necessarily three you can expect:
- Aperture value, or hole size through which your camera sees view
- Shutter speed, or how long the shutter remains open to light
- The amount of light in your view
These three factors determine how much light hits your sensor. And this is certainly the most important thing that determines the image quality: how much light you captured to describe the scene. This is not the end of the story, though.
What about ISO?
Your camera also has a setting called ‘ISO’ that determines how light or dark your last image looks. So if you are shooting in low light, you can increase the ISO to make the image lighter. But keep in mind that changing the ISO does not increase the amount of light you captured: it just tries to create for the fact that you cannot capture more.
| Pentax K -3 Mark III | Pentax 15 mm F4 Ed Al | ISO 32000 | 1/30 seconds | F8 Adobe camera left for default with noise edited noise in RAW Photo: Kerry Rose |
As the level of light falls, your images will be found due to lack of light. ISO can’t really help with it, but it is No noise causes,
shutter speed And the effect of each aperture is on what the final image looks. Once you understand those effects, you can learn the balance act required to get as much exposure as you can, then use ISO to try to make a difference.
