Imprinting videos with your personal style starts with making sure you capture your images the right way. An important part of this process involves learning everything about exposure and how to handle the different elements that play a role in exposing your images. Having this knowledge and mastering it on your day to day work will make things significantly easier for you both during shootings and down the line in post production. Below, we break down the three main elements that, together, determine the level of exposure in most cameras.
The first factor that influences exposure on an image is aperture. If you are not familiar with the concept of aperture, then perhaps you may have heard of the f-number or f-stop. Basically, the aperture in photography and filmmaking refers to the amount of light that you let reach the sensor or film. In most cameras, you can control this using the diaphragm, which in turn will gradually open and close to a certain extent. The stops at which the diaphragm closes or opens correspond to f-numbers, which in turn determine the depth of field of the image at any given aperture. Wider apertures let more light in, thus giving us better exposure.
Next up is the shutter. Think of the shutter as a window that can only be fully open or closed. The house where this window is will get cooler the longer you keep it open. In a camera, it works the same way, except it is the film or the sensor the thing that will get more or less exposure depending on the speed at which you adjust the shutter. Setting up a higher shutter speed means that the device will open and close more quickly, thus letting in less light, while lower speeds will have the opposite effect.
Lastly, the ISO value of the camera is, simply put, referred to the sensitivity of the sensor. It was modeled after the standards for film exposure, so the settings are as close to the real thing as they can be. Your typical digital camera has a range of ISO values that determine the exposure index of the footage you will be filming. This range usually starts at 100 in most cameras, and goes up to the 1000s and even to the 10000s depending on the model you work with. Choosing the higher values in your ISO scale will give you a brighter image, but it will also introduce significant levels of noise or grain to your image, which in turn will noticeably lower the quality of your images.
The histogram in your camera is a graphic representation of the brightness levels of your image. It covers a spectrum that, in terms of exposure, shows you everything from underexposed to overexposed images. What you want to capture is up to you, so there is really no right or wrong when it comes to exposure. However, if you don’t want any parts of your image to be pitch black with no detail or completely bright and burnt, then always keep away from both extremes of the histogram and try to stay within the mid tones.