Aperture and Depth of Field

The aperture controls the amount of light hitting the sensor. It is measured in f-stop and typically ranges from f/1.8 to f/22 (f/1.8 being a very large aperture and f/22 being a very small aperture – imagine a large hole like a bottle top for f/1.8 versus a pinprick for f/22). The depth of field is much higher when more light is let in, so f/1.8 has the shallowest depth of field and therefore more background/foreground blur (depending on focus point). The opposite being a great depth of field at f/16 – f/22 has generally everything in focus. Depth of field and aperture link in directly with each other – aperture is the number you control based on the scene and the effect you want – and the depth of field is what is produced based on that number (also the level of exposure in the image.)

Above is the canon camera simulator this is a low aperture photo I have taken – to use the large aperture which lets lots of light in I had to use a higher shutter speed – (1/250 or higher is typically good for action photography) and a lower ISO. This large aperture creates a narrow depth of field and only the plane and a few marbles are in sharp focus – in my opinion this creates a higher quality effect.

This has a medium aperture which means the image still has a narrow depth of field but the image is not as blurred.

This is a very high aperture photo which means it has a very large depth of field and the whole image is in focus.

(FOCAL LENGTH AND FOCUSING)

Focal length is the length is the distance between the pole of the mirror and the focal point of the mirror. A higher focal length leads to a ‘flatter’ image. 50mm focal length is ideal for portraiture photography because it replicates the human eye and is therefore the most flattering – but a lower photo length leads to a wider image. The focussing ring allows you to change what is in focus in the image. You adjust it until either the whole image is blurred (Uta Barth) or the section you want in focus is sharp. There is also autofocus which is another setting where the camera focus’ on what it in the centre when you half press the shutter button.

PHOTOGRAPHERS WHO USE INTERESTING APERTURE AND MANUAL FOCUS

Uta Barth is a photographer that has a very unique style and generally takes photos of out of focus scenes. It is very abstract. She clearly uses the focus ring to force the camera out of focus which creates a cool effect. She is a contemporary German-American photographer who explores optical illusions, visual perception and non-place. She emerged in the late 1980s and brought light to the viewers visual attention within the photography frame. She takes photos of surreal landscapes and roads, in a deliberately blurred, dreamy way. Her works are exhibited internationally for their unique style and aesthetic look.

Ralph Eugene Meatyard is a photographer that has a similar style of work to Uta Barth but this set of images called “Zen Twigs” he made sure to keep one twig in focus in the foreground. This creates a sense that the branch is the most important thing in the image and creates a cool effect.

Saul Leiter was a photographer who was formerly an artist and then discovered photography. He uses lots of unusual framing devices in his images like windows and signs to draw our eyes to a large section of blur and draw our eyes to a splash of colour.

MY PHOTOSHOOT