In photography, exposure is a word to describe the amount of light that reaches the photographic film or sensor. Exposure is created by using the Aperture; the size of the lens opening, the shutter speed; the length of time the shutter is left open and the ISO; the sensitivity of the film or sensor. This is known as the exposure triangle.
The “correct exposure” is simply an expression to state that the photographer found the correct balance in the setting to portray the scene to his or her liking. When I first started my journey into photography, finding the right mix was a blessing and a curse. There is no set standard to an exposure because the light always changes as well as the photographers creative vision. However, over the years I came across helpful tips in finding a good starting point for each of my shoots. For more information please visit Sunny 16 and Loony 11 . Using these two tips will get get you the most accurate exposure to the scene in front of you. From there change your settings until they match your vision.
For example you wouldn’t use the same shutter speed, ISO, and aperture settings to capture a still flower in a meadow as you would to capture details in a fast moving car. In order to capture the details of the car you would have to do one of three things: raise the ISO and shutter speed, lower the aperture and raise the shutter speed, or lower the aperture, raise the shutter speed and the ISO in order to balance out the light and counteract the movement.
Here is a chart to get you started on judging movements and starting points for your shutter speeds, remember this is only a guide. Your speeds will more than likely change due to the fact that weather, time of day and available light is continuously changing.
Every time you make an adjustment to one of your settings you will need to compensate for it with the other settings. A good practice for a photographer to do is meteor your scene “as is” then adjust your setting to compensate for that is going to happen in the scene.