We have all seen amazing photographs with striking foregrounds while the background blurs to oblivion. That blurred background, commonly referred to as Bokeh, can be controlled by setting your camera aperture effectively. We typically recommend lenses with a maximum aperture of at least f/2.8 because it gives you more creative flexibility and low light possibilities.

We have all seen amazing photographs with striking foregrounds while the background blurs to oblivion. That blurred background, commonly referred to as Bokeh, can be controlled by setting your camera aperture effectively. We typically recommend lenses with a maximum aperture of at least f/2.8 because it gives you more creative flexibility and low light possibilities.

Aperture dictates the available area in focus (depth of field) as you move away from the camera. Typically, when you focus at a given area, 1/3 of your ‘in focus area’ will be in front of the focus point, while 2/3 of the area will remain behind the focus point. This is very important because it ensures that you keep the important aspects of your image in focus while leaving the other distracting backgrounds elements. Aperture also controls the amount of available light the reaches the image sensor. This often leads to a tradeoff, especially when shooting indoors or in low light between available light and areas in focus. There are plenty of depth of field calculators available online or for most smartphones. These calculators will help you determine the available depth of field based on your lens, distance from the focusing point, and set aperture. When shooting at very wide apertures especially, it is imperative to know your focusing point. We will take a closer look at focusing in another lesson but a quick and easy way of ensuring correct focus is to select a focus point, and aim that point at your subject. If your subject is very close to the camera lens, you can expect a very small depth of field. In this case, you may need to alter the aperture settings to ensure your subject remains in focus. Also, if you are photographing a moving subject, your focus point may be shifting constantly make it difficult to achieve sharp photos at very wide apertures.

Lighting conditions affect almost all aspects of your photo and it is important to ensure that you have the correct amount of available light reaching the camera’s image sensor. This is another reason we typically recommend lenses with apertures of f/2.8 minimum because it allows you the flexibility of shooting with low amounts of available light. Many times, a typical kit lens simply will not allow you the ability of shooting indoors in many cases. Increasing your camera ISO will pull the image brightness back up to normal, but often with considerable loss of detail and increased noise in your image. Controlling your aperture in conjunction with shutter speeds and ISO settings will ensure that you have a properly exposed image, with the important areas in focus, at fast enough shutter speeds to ensure sharp results.

Another critical factor often overlooked is lens capability. Just because a lens spec sheet says it can shoot at f/1.2 doesn’t mean you will get sharp results at that settings. Most lenses have a sweet spot between f/4-f/8 producing the best quality results at those settings. It is important to know the capabilities of your lens to ensure you will get appropriate results at any given settings. Often, if the situation allows for it, it may be better to shoot at f/4 instead of f/2.8 solely because of the increased sharpness and contrast of the lens at f/4.

LearingCameras.com will be adding lens reviews every week to ensure our readers remain informed. This beginning guide to aperture will help you understand the basics of how your lens and camera works. This subject is a very complicated one with many different opinions based on shooting styles and locations. As a result, we will continually be updating this topic with more information and examples. Please submit any questions you may have and we will answer those questions in future articles.