Understanding Exposure

How Aperture, Shutter Speed, and ISO work together for creating a properly exposed photograph:

1: Aperture is the measure of how open or closed the lens’ iris is. A wider aperture (smaller f-number) means more light will be let through the lens, simply because the opening is larger. A narrower aperture (higher f-number) allows less light to reach the sensor (or film).

Aperture also controls the depth of field in an image (how much of the scene is in focus). The smaller the aperture opening, the more that will remain sharp in the final image. This is great for landscapes, but can be distracting for close portraits.

2: Shutter Speed is a measure of how long the shutter will remain open and thus, how long the sensor (film) is exposed to light. Faster shutter speeds give the sensor less time to collect light, and result in a lower exposure.

Faster shutter speeds are stylistically used to stop motion, whether this is to avoid camera shake while hand holding the camera, or to capture a fast moving subject. Remember, as long as the shutter is open, the camera is recording the position of the elements in the frame; if those elements are moving, the result will be blurriness.

3: ISO is slightly more difficult to articulate, but an easy concept to grasp. It’s originally a number to describe the sensitivity of the film used. This would be a static number. Once loaded, only aperture and shutter speed were available to make a proper exposure. Now with modern digital cameras the ISO value can be controlled at will giving more flexibility in changing lighting conditions.

Increasing ISO essentially allows you to work with less light. As always, though, there’s a tradeoff. Increasing ISO results in increased noise and less detail in the image.

EVs and Stops are the combinations of the 3 sides of the exposure triangle. EV stands for Exposure Value, and often refers to the change that either doubles or halves the amount of light reaching the sensor (or double/halves the sensitivity) as a stop.

Shutter speeds and ISO respond numerically how one would expect: a change from ISO 200 to 400 is an increase of one stop; a change of shutter speed of 1/15s to 1/60s is a decrease of two stops. However, f-stops, which correspond to aperture, are arranged in a geometric series that roughly approximates powers of the square root of two. In other words, the following sequence, each new f-stop represents a decrease of one stop: f2, f2.8, f4, f5.6, f8, f11, f16, f22. It’s best to just memorize this sequence to intuitively work with “doubling” or “halving” an f-stop.

An Introduction to Composition

The Rule of Thirds 

Aligning objects to a certain grid in your photos will add balance and intrigue to your work. To do this, you must imagine your photo is divided into a grid of 9 equal parts, like the image below.

Next, frame your image to adhere to these dividing lines both vertically and horizontally as best you can. You can also adjust the image to feature key elements at intersections.

Leading Lines 

As humans we are drawn to lines and symmetrical objects, therefore by taking photos based off of leading lines, it can help improve your composition. Common leading lines could include roads, train tracks, waterways, and other lines that can guide the eye through an image.

They don’t have to be completely straight though. For a more interesting leading line try a windy road or curved river. Find ways to lead lines to your subject or creatively tell a story.

Perspective Change

Shooting from a standing position may be easy, but it’s also what we’re most used to seeing. A better option is to get high or low, and produce an image from a perspective that’s new. This will be result in a powerful image that’s more interesting to the viewer.

Patterns

Taking a photo that involves patterns can quickly draw people in. The contrast and pattern in the image below make it both eye-catching and different from the usual photos of a lake or pond.

Look for patterns in both urban and rural environments, you’d be surprised what you can find! Patterns can come about in the form of colours, shapes, unique alignments, and more.

Break the Rules

Rules are made to be broken, and sometimes following the rules doesn’t result in the best image possible.

It’s always best to experiment and take lots of photos. Eventually creating interesting compositions will be come second nature.