The Basic SLR

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1 The Basic SLR ISO Aperture Shutter Speed Aperture The lens lets in light. The aperture is located in the lens and is a set of leaf like piece of metal that can change the size of the hole that lets in light. Aperture The aperture controls how MUCH light enters the camera. This opening is inside the LENS of the camera and is adjusted by a ring on the outside of the lens. The larger the opening the less sharp the final image will be; the larger the opening the more light that is allowed into the camera. Apertures on the common camera f/1.4 f/2 f/2.8 f/4 f/5.6 f/8 f/11 f/ F- Stops are a unit used to quantify ratios of light or exposure, with one stop meaning a factor of two, or one-half. The one-stop unit is also known as the EV (exposure value) unit. On a camera, the f-number is usually adjusted in discrete steps, known as f-stops. Each "stop" is marked with its corresponding f-number, and represents a halving of the light intensity from the previous stop. This corresponds to a decrease of the pupil and aperture diameters by a factor of or about 1.414, and hence a halving of the area of the pupil.

2 Depth of field test on a Nikon 60mm lens This test is not designed to show you a precise measurement of the depth of field, since the ruler is actually at an angle. It simply shows you how the depth of field increases. Notice how the boundary between the in-focus area and the out-of-focus area becomes less defined as the aperture gets smaller. The test is done fairly close to 1:1 magnification. F4 F16 F40

3 Shutter Controls how LONG light enters the camera. This is TIMED by the shutter speed dial, usually on top of the camera. The larger the number the SHORTER the time. A short time lets in light quickly which will stop the MOTION an object might have as it travels across the Lens of the camera while being exposed. Shutter Speeds on the common camera B Each speed is a fraction of a second - like 1/1000th of a second or 1/4 of a second. B stands for bulb and holds the shutter open as long as the shutter release is held down. Each shutter speed lets in half as much light at the one below it to allow for easier exposure calculations. Shutter speed is measured in seconds or in most cases fractions of seconds. The bigger the denominator the faster the speed (ie 1/1000 is much faster than 1/30). In most cases you ll probably be using shutter speeds of 1/60th of a second or faster. This is because anything slower than this is very difficult to use without getting camera shake. Camera shake is when your camera is moving while the shutter is open and results in blur in your photos. If you re using a slow shutter speed (anything slower than 1/60) you will need to either use a tripod or some some type of image stabilization (more and more cameras are coming with this built in). Shutter speeds available to you on your camera will usually double (approximately) with each setting. As a result you ll usually have the options for the following shutter speeds 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8 etc. This doubling is handy to keep in mind as aperture settings also double the amount of light that is let in as a result increasing shutter speed by one stop and decreasing aperture by one stop should give you similar exposure.

4 Shutter speed settings. First at the 40 shutter setting: the exposure time is 1/40sec - about quarter the length of a blink - yet it is too long to capture the fast-moving water, so it is milky blurred.125 or 1/125sec is a good average short exposure, but it s not enough to stop the water. We need an exposure much shorter to freeze the movement. A 500 setting or 1/500sec exposure does the trick: we can see individual streams of water caught sharply 40 (1 / 40 th of a second) 125 (1 / 125 th of a second) 500 (1 / 500 th of a second)

5 Composition There are many different ways where the rules of composition can drastically change the look and feel of a photograph. These rules need to be learnt if you want to improve your photography and only then can you begin to break them. One of the simplest ways of improving your photography is called: The rule of thirds The basic principle behind the rule of thirds is to imagine breaking an image down into thirds (both horizontally and vertically) so that you have 9 parts. As follows: Looking through your viewfinder imagine the frame split up into imaginary thirds. With this grid in mind the rule of thirds now identifies four important parts of the image that you should consider placing points of interest in as you frame your image. The theory is that if you place points of interest in the intersections or along the lines that your photo becomes more balanced and will enable a viewer of the image to interact with it more naturally. Studies have shown that when viewing images that people s eyes usually go to one of the intersection points most naturally rather than the center of the shot using the rule of thirds works with this natural way of viewing an image rather than working against it

6 Example of rule of thirds Other elements to help with composition are natural lines that lead into the frame. Framing an image can enhance your photographs.

7 The above subject in this photograph looks as if she is running out of space within the frame. By simply re-framing the image we give more space to the subject which enhances the whole composition. Using the rule of thirds and simply reframing our subject, placing the sailing boat to the left of the frame and then moving the Horizon along the third line from top or from the bottom, we can enhance our photographs with ease. See below (next picture)

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9 Other methods to help with composition. LEAD IN LINES! Using the shadows from the horse we can use them as lines that lead into the photograph. We can also enhance our photographs by using the natural landscape to frame our subject. In this case the landscape leads into the middle of the frame where our subject is. USING THE FOREGROUND! This photograph is enhanced by placing something of interest in the foreground. In this case the odd looking lampshade is framed in the top right hand third of the image. Giving the photograph balance as well as making the photograph more interesting to look at.

10 SPOT COLOUR The above image has been enhanced by the photographer being aware of the contrast of colours with the frame. The colours of the flags look as though they re jumping off the surface of the photograph.

11 2 nd day Photo-shoot brief Your assignment is to take 12 Shots to produce for critique! Aperture One Shallow depth of field (F4) One medium depth of field (F8) One long depth of field (F22) Shutter Speed One showing movement (30 th of a second) One freezing the action (500 th of a second or above) Panning shot (following the action. i.e a car, animal, runner or cyclist) Composition 2 x Rule of thirds. One in landscape and one portrait 1 x fill the frame! Change of viewpoint (the same image but from 2 different angles) Break the rules! Pick your 10 best shots and write down the number so that you course trainer can quickly find the images that you want to display

12 .and finally! Please ask your course trainer if you would like any additional training on anything you have covered within the past two days. Suggested topics for further reading: White balance Lighting Raw files Photoshop Exposure compensation We would recommend gathering some information and looking at the work of the following photographers: Michael Langford Basics of digital Photography Andy Rouse Wildlife Martin Parr Documentary Richard Avedon or Edward Karch Portrait Photography.have fun, get out there and explore!