Learning About F-Stop


The best way to learn something is by doing it. Learning the ins and outs of the camera is no different. The technicalities of aperture, ISO, and shutter speed can be difficult to grasp when reading about them online. Simplified, each of these settings work together to produce the level of light, known as exposure, revealed in your photographs. We decided to illustrate aperture, which is the size of the opening of the lens, by taking a series of photographs and increasing the f-stop each time. This exercise can be replicated using at least 3 objects that are similar in size. We decided to use 5 rolled up cash bills. The objects are then placed equidistant from one another, each item an equal step back away from the position of the camera.

Once your objects are set up, the experiment begins! The challenge of this exercise is maintaining the same level of exposure in each image. Keep in mind that as you increase the f-stop number, the aperture opening gets smaller and less light is let in. In order to maintain exposure levels, you need to incrementally decrease the shutter speed to let in more light over the time of your shot. Start with the lowest f-stop your lens can achieve; our Canon 50mm lens reaches an F2.8. Focus on the closest object, test the lighting, and adjust your ISO and shutter speed to achieve the exposure that you want. Once you’re satisfied with the first image, increase the f-stop to the next level, and decrease the shutter speed to compensate for the lighting change. Repeat these steps until you go through as many f-stop levels as you’d like. Once complete, you’ll notice that as you increase the f-stop, your depth of field widens, and more of the objects are in focus. Send us photos of your tests, and keep learning!

Cameron Kirkland