Why There is No Such Thing as a Correct Exposure
Perhaps the most common question all beginner photographers ask is “What exposure settings do I use to get the correct exposure?” Simply put, they want to know what specific ISO, shutter speed and aperture settings to use to get their photograph “correct.” Somehow, they feel that if they don’t use the right settings, their photo will be “wrong.”
Photography is not like math, there is no correct answer when it comes to taking a photo. You can’t plug the exposure settings into an equation and always get the same answer. If you could then a machine could replace photographers, you wouldn’t want a machine to do your job would you?
To help bring this point across, I posted up a quiz the other day where I posted the two photos below and asked people to choose which photo represented the “correct” exposure.
The quiz was actually a "trick" question. Both photographs are exposed “properly.” Neither is wrong.
While the results weren’t exactly what I was expecting (there was only 23 votes at the time of this writing), they do show that there isn’t a straight answer when it comes to having a “correct” exposure. 70% voted for photo A, while 30% voted for photo B. Any discrepancies really have to do with “taste” as far as which type of photo people prefer and not to do with exposure differences.
The point of the quiz was to show you that either answer is correct. There is no one "correct exposure." I don't want you to think about getting the "correct exposure." Really, just block that idea from your mind.
An exposure can be taken many different ways
Remember, an exposure can be taken with many different combinations of ISO, shutter speed and aperture settings that will give you the same exposure value (based on your camera’s light meter). For example, you can use a high aperture with a low shutter speed, or you could use a fast shutter speed with a low aperture. You can change your ISO to further add into the mix.
When you look at a scene in front of you, there will be countless ways which you can record that image. How you choose to photograph it, is totally up to you. That is where the creative element of photography comes in - and that element is totally within your control.
Instead of asking, "what exposure settings are correct?" Ask yourself, "what creative result do I intend?"
- Do you want to freeze motion or blur motion?
- Do you want shallow depth-of-field or great depth-of-field?
- Do you want a noisy image or a noise-free one?
These creative effects can all be controlled based off of what exposure settings you choose. And no machine can ever replace that.