Session 3 Aperture (Photography Class)

Aperture

Prae-Lectio: Aperture

•  Concept of Aperture •  Exposure Triangle •  What is an aperture •  Depth of Field

What is an aperture •  The aperture is the hole

(opening) in the lens that the light passes through.

•  Apertures available depend on the lens, and are usually changed by rotating a collar on the lens close to the camera.

•  Aperture is the lower ring, the focusing ring is the upper.

•  The larger the aperture number, the smaller the hole and so the less light can get through.

Aperture Ring

Aperture - Achieving the correct exposure is a lot like collecting rain in a bucket. While the rate of rainfall is uncontrollable, three factors remain under your control: the bucket's width, the duration you leave it in the rain, and the quantity of rain you want to collect. - You just need to ensure you don't collect too little ("underexposed"), but that you also don't collect too much ("overexposed"). - The key is that there are many different combinations of width, time and quantity that will achieve this.

How the Aperture Works

Exposure Triangle

Aperture

Aperture Stops

How to Set Your Aperture

Desired Opening

Apertures

Depth of Field •  One of the powerful tools of your

lens is the Depth of Field, it can be used to keep things sharp and also isolate something from the background.

•  Take this image as an example, I captured it at a tire "graveyard”. The picture really was about a lonely flower among all the tires. This frame was shot at f/11 but at this aperture it was really hard to see the flower. In fact, it was almost hard to make out what I was looking at.

Depth of Field

•  In this picture I opened up wide to f/2.4. Notice how the flower in the foreground now are jumping out of the image while it is still possible to see the tires in the background, but now the tires are more of texture and support to the flower.

Depth of Field •  The aperture controls the “depth of

field” in the photograph. When you focus on a particular point, all points that distance from the camera are in focus. Points closer and further away may also be in focus, depending upon the aperture. At narrow apertures, more of a scene is in focus, useful in a landscape where you want the foreground and background in focus. On the other hand, when taking a portrait, using a wide aperture will put the distracting background out of focus, isolating and emphasizing your subject.

Depth of Field •  Less Depth of Field: With the

lens focused on the side of the bench, the aperture of f/1.4 throws just about everything else out of focus. Notice the benches in the distance and the plant in the bottom left corner. A wide aperture is often used in portraiture or whenever a subject needs to stand out from its surroundings.

•  Lots of Depth of Field: An aperture of f/16 results in everything being in focus. Narrow apertures are often used in landscapes to make everything from the foreground to the sky in focus.

Aperture Table (f stops) Aperture Remarks

2 Wide, very little depth of field, some are out focus, with emphasis on something

2.8

4

5.6

8

11

16

22 Narrow, lots of depth of field, almost all are in focus

Apertures

Depth of Field

A small aperture provided this image with plenty of depth of field, using ISO 400.

Play of Light and Shadow

A small aperture provided this image with plenty of depth of field, using ISO 400.

Aperture: Depth of Field

Repetitio: Aperture

•  Concept: A bucket of water •  Control the entry of light •  Higher Number – smaller aperture •  Depth of Field •  Smaller aperture – more depth of field