In week two of Digital Photography, we began our journey into a more in-depth understanding by examining exposure and the importance of light.

There is no photography without light

Ben Long

Exposure

Without the presence of light, photography would not be possible. It is through the control of light and understanding exposure that we can capture images (Long 2018). Exposure dictates how much light or darkness is visible to your camera and in photography is comprised of the exposure triangle which includes; Shutter speed, Aperture and ISO (McHugh 2018).

Shutter Speed

The shutter speed is the amount of time that the shutter remains open during an exposure and how much light is allowed in. The faster the shutter speed, the quicker it captures an image, while the slower it is, the more time it takes. Long shutter speed will provide more light, at the cost of motion blur (which can be used creatively in the capture of water, night/stars and usually requires a tripod to limit movement or shake) (Gibson 2011).

Shutter Speed is measured in a range of 1/8000 of a second to 1 to 30+ seconds (McHugh 2018) and can vary depending on the camera.

Aperture

The aperture is an iris which controls how much light is allowed into the lens. If the iris is opened wide, more light is passed through, while a smaller iris means less light. The measurement of the aperture, however, calculates how much light is being stopped, with less light being a larger f-stop (Long 2018). The aperture also controls the depth of field, or how sharp scenes appear. A low f-stop setting provides a shallow depth of field, and a high f-stop value shows a widespread depth of field (McHugh 2018).

Aperture is measured in f-stops in a range of f/1.0 to f/5.6 (McHugh 2018), but can vary depending on camera and lens.

ISO

ISO is the sensitivity of the camera’s sensor to light. The higher the ISO, the more light. However, it is always prefered to have the lowest ISO possible, because the higher the number, the more noise or grain that becomes visible (McHugh 2018).

ISO is measured in speeds of 100 to 3200 (or higher) (McHugh 2018).

Camera Metering

The camera metering refers to a light meter inside the camera which evaluates the light in a scene. Cameras typically include spot, evaluative (matrix) and center-weighted (McHugh 2018).

Histogram

The histogram is a graph that is visible on the LCD screen of the camera which represents the brightness. It measures from left to right; darkness, shadows, mid-tones, highlights and white (Gibson 2011). A histogram is a valuable tool because it shows you the exposure levels and allows you to determine if an image is under or overexposed. Viewing a preview of an image may allow you to determine the aesthetic value of the picture, however, the histogram can calculate the exposure in a more precise way. Which is helpful if you can’t view your screen correctly.

Thoughts

There has been a lot to absorb this week about photography and exposure. The more I step outside and capture in manual mode, the more familiar and intuitive it becomes to know about different settings. It does not mean that I am doing to capture good exposure each time, but it allows me to understand why and how it is possible.

I also found it was one thing to learn about exposure and another thing to do it. When you have your camera, there are a lot of variables that come into play. Sometimes you don’t have a lot of time to capture a particular subject (such as an insect), so it’s easy to get confused. I am sure that the more I practice, the better I will become.

Task

The task for week two requires us to take three photographs which employ the use of exposure techniques to capture motion.

1x Image that suspends motion using a fast shutter speed

1x Image that captures motion using a slower shutter speed

1x Image that implied motion by capturing the subject and blurring the background (pan)

Week 2 Photographs

Along with the task, I have also taken more photographs this week. All pictures are original and not retouched, only resized.

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References

Gibson, A. (2011). Exposure and Understanding the Histogram  

Long, B. (2018). What is exposure? Photography Foundations: Exposure (part 1). Lynda.com: https://www.lynda.com/Photography-tutorials/What-exposure/734659/801226-4.html?autoplay=true.

McHugh, S. T. (2018). Chapter 1: Basic Concepts in Photography Understanding Photography: No Starch Press.