What is Fstop?
Just like any other profession, photography has its own language. When you hear a photographer say about the word ‘aperture’, or something like the ‘fstop’, then you are hearing photography lingo. Fstop and aperture have the same meaning in photography. Aperture or fstop refers to the opening of the lens of a camera. When photographers talk about the fstop, it means an expression that is used to measure the amount of light coming in from the lens of the camera.
Every camera has lens that is an important part in recording or capturing images. Light is an essential element for capturing images. Without light, it would not be possible for cameras to take pictures. Exposure is vital to produce the desired result for a photograph. It is the function of the fstop to regulate the exposure for the production of an image. By means of the fstop an image is produced being neither too dark nor too light.
The ‘f’ in the term Fstop refers to focal length. Fstop number measures the light coming through the lens. Fstop is measured by dividing the focal length by the diameter of the pupil. Fstop is often expressed with the letter f over a number, i.e. ‘f/4’ or ‘f/3’. The number which appears after the letter f represents the width of the aperture. You may compare the aperture of a camera to the pupil of the eyes. Depending on the amount of light needed, it can dilate wider or narrower. When the fstop number is larger, it means the aperture or the opening of the lens is narrower, and vice versa. Therefore, f/4 means the aperture is narrower that f/3.
In photography, there is a known technique called reciprocity. The technique uses opposite methods resulting to the same properly exposed photo. A camera set to a narrow aperture and a slow shutter speed will have the same photo result as an aperture set wider and faster shutter speed. Fstop is also related to the term ‘depth of field’.
Depth of field is also important when taking pictures. The term refers to the amount of visible background behind a main subject in the photo. If a photographer wants to take a picture of a small plant in a garden, setting the fstop wider with faster shutter speed will blur the background. The small plant will be in sharper focus. On the other hand, if a photographer wants to shoot at a group of people in front of a great view, narrow fstop and slow shutter speed must be set. This will result to an image with sharp focus on both the group of friends and the background.
In photography, fstop and shutter speed work hand in hand. To produce the desired result of an image correct fstop and shutter speed settings must be utilized. Generally, photographers follow the ‘sunny 16’ rule in which the camera is set to f/16 and shutter speed must match up the film speed. Digital cameras have automatic settings wherein the ISO and shutter speed are set the same to get perfectly exposed photos at all times.