How Exposure Works
What is exposure and how is it used? When trying to take a photo at a professional standard, there are some factors in photography that will benefit. When using a high-end digital camera, there are 3 key parts you will need to know. Having a clear understanding on the basics of photography will guarantee a great picture. Here are the 3 most important things that are in a camera;
Aperture
Shutter Speed
ISO
Aperture
What is Aperture? In a camera lens, there is a hole that opens and closes. The size of the aperture is determined on how big or small the hole is. The larger the hole, the more light is allowed in, and vise versa. When we measure aperture, we measure aperture in f-stops. For example, if I would have set my f-stop to f/22, my opening would be smaller. However, if I set my f-stop to f/4, my opening would be larger. Furthermore, aperture is mostly connected with an image’s depth of field (DOF), the amount of the image that is focused. Now, talking about f-stops, choosing a smaller f-stop number, you will allow the camera to have achieve a smaller DOF.
Shutter Speed
What is Shutter Speed on a camera? When we are talking about shutter speed, we are talking about the amount of light is being allowed inside the camera. If you think about blinds, the longer you leave them open, the more light is coming in. Going back to what I said about aperture, the shutter speed and aperture work very closely together. The aperture detects the amount of light that’s being allowed in, whereas the shutter speed lens opens and closes to allow the light to hit the sensor.
Furthermore, shutter speed is measured in fractions of a second (e.g 1/30-1/1000), you are basically telling your camera how quickly or slowly to open or close the lens. If you set your shutter speed to 1/60, you will allow your camera to capture images that have a blurry effect. For example, if I took a picture of a moving car, the car will still be focused but the background will be blurred. This creates a interesting blurry effect. However, if I set my shutter speed to 1/250, this will capture images that are fully focused. (Try use a tripod if shutter speed is set on 1/60 for more accurate shots.)
ISO
What is ISO? ISO stands for International Standards Organization and this basically means the camera’s sensitivity to light. The higher the ISO, the more sensitive it is. This is measured according to international standards, so ISO100 on one camera will be exactly the same as ISO100 on another. Each ISO setting is double the one before: if you increase the ISO from 100 to 200, you double the camera’s sensitivity; and if you increase it from 200 to 400, you double it again. This carries on through the ISO scale.
Bibliography
http://www.itsjustlight.com/photography-course/making-sense-of-exposure/
