1. Cameras The basics

2. SLR Camera Diagram 1. A typical digital SLR camera

3. Cross section of a digital SLR Diagram 2. Cross section of a digital SLR

4. Exposure triangle ISO - the measure of a digital camera sensor’s sensitivity to light Aperture - the size of the opening in the lens when a picture is taken Shutter Speed - the amount of time that the shutter is open It is at the intersection of these three elements that an image’s exposure is worked out.

6. Most importantly - a change in one of the elements will impact the others. This means that you can never really isolate just one of the elements alone but always need to have the others in the back of your mind.

7. Metaphors for the triangle The Window Imagine your camera is like a window with shutters that open and close. Aperture is the size of the window. If it’s bigger more light gets through and the room is brighter. Shutter Speed is the amount of time that the shutters of the window are open. The longer you leave them open the more that comes in. Now imagine that you’re inside the room and are wearing sunglasses (hopefully this isn’t too much of a stretch). Your eyes become desensitized to the light that comes in (it’s like a low ISO).

8. Sunbaking In a sense your skin type is like an ISO rating. Some people are more sensitive to the sun than others. Shutter speed in this metaphor is like the length of time you spend out in the sun. The longer you spend in the sun the increased chances of you getting a tan (of course spending too long in the sun can mean being over exposed). Aperture is like sunscreen which you apply to your skin. Sunscreen blocks the sun at different rates depending upon it’s strength. Apply a high strength sunscreen and you decrease the amount of sunlight that gets through - and as a result even a person with highly sensitive skin can spend more time in the sun (ie decrease the Aperture and you can slow down shutter speed and/or decrease ISO).

9. Aperture Hole or opening through which light is admitted.

10. Basics of Aperture When you hit the shutter release button of your camera a hole opens up that allows your cameras image sensor to catch a glimpse of the scene you’re wanting to capture. The aperture that you set impacts the size of that hole. The larger the hole the more light that gets in - the smaller the hole the less light.

11. How aperture is measured Aperture is measured in ‘f-stops’. You’ll often see them referred to as f/number - for example f/2.8, f/4, f/5.6,f/8,f/22 etc. Moving from one f-stop to the next doubles or halves the size of the amount of opening in your lens (and the amount of light getting through). Keep in mind that a change in shutter speed from one stop to the next doubles or halves the amount of light that gets in also - this means if you increase one and decrease the other you let the same amount of light in - very handy to keep in mind).

12. Confusion about apertures One thing that causes a lot of new photographers confusion is that large apertures (where lots of light gets through) are given f/stop smaller numbers and smaller apertures (where less light gets through) have larger f-stop numbers. So f/2.8 is in fact a much larger aperture than f/22. It seems the wrong way around when you first hear it but you’ll get the hang of it.

13. Aperture – decreasing aperture, increasing f #

14. Aperture and Depth of Field Depth of Field (DOF) is that amount of your shot that will be in focus.

15. Large depth of field means that most of your image will be in focus whether it’s close to your camera or far away.

16. Large DOF illustration

17. At first thought you might think large depth of field is always the way to go so you have as much of the photograph in focus as possible, but this is not true. Shallow depth of field can be very useful in a lot of situations and in certain styles of photography.

18. Shallow Depth of Field Small (or shallow) depth of field means that only part of the image will be in focus and the rest will be fuzzy

19. For example in most landscape photography you’ll see small aperture settings (large numbers) selected by photographers. This ensures that from the foreground to the horizon is relatively in focus. On the other hand in portrait photography it can be very handy to have your subject perfectly in focus but to have a nice blurry background in order to ensure that your subject is the main focal point and that other elements in the shot are not distracting. In this case you’d choose a large aperture (small number) to ensure a shallow depth of field. Macro photographers tend to be big users of large apertures to ensure that the element of their subject that they are focusing in on totally captures the attention of the viewer of their images while the rest of the image is completely thrown out of focus.

20. ISO In traditional (film) photography ISO (or ASA) was the indication of how sensitive a film was to light. It was measured in numbers (you’ve probably seen them on films - 100, 200, 400, 800 etc). The lower the number the lower the sensitivity of the film and the finer the grain in the shots you’re taking.

21. ISO in Digital In Digital Photography ISO measures the sensitivity of the image sensor. The same principles apply as in film photography - the lower the number the less sensitive your camera is to light and the finer the grain. Higher ISO settings are generally used in darker situations to get faster shutter speeds (for example an indoor sports event when you want to freeze the action in lower light) - however the cost is noisier shots.

22. ISO Examples The one on the left is taken at 100 ISO and the one of the right at 3200 ISO. 100 ISO is generally accepted as ‘normal’ and will give you lovely crisp shots (little noise/grain).

23. Questions to ask When choosing the ISO setting generally ask the following four questions: Light - Is the subject well lit? Grain - Do I want a grainy shot or one without noise? Tripod - Am I use a tripod? Moving Subject - Is my subject moving or stationary? If there is plenty of light, I want little grain, I’m using a tripod and my subject is stationary I will generally use a pretty low ISO rating.

24. However if it’s dark, I purposely want grain, I don’t have a tripod and/or my subject is moving I might consider increasing the ISO as it will enable me to shoot with a faster shutter speed and still expose the shot well.

25. Situations where you might need to push ISO to higher settings include: Indoor Sports Events - where your subject is moving fast yet you may have limited light available. Concerts - also low in light and often ‘no-flash’ zones Art Galleries, Churches etc- many galleries have rules against using a flash and of course being indoors are not well lit. Birthday Parties - blowing out the candles in a dark room can give you a nice moody shot which would be ruined by a bright flash. Increasing the ISO can help capture the scene.

26. Shutter speed Shutter speed is the amount of time that the shutter is open. In film photography it was the length of time that the film was exposed to the scene you’re photographing and similarly in digital photography shutter speed is the length of time that your image sensor ’sees’ the scene you’re attempting to capture.

27. 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).

28. 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.

29. 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).

30. When considering what shutter speed to use in an image you should always ask yourself whether anything in your scene is moving and how you’d like to capture that movement. If there is movement in your scene you have the choice of either freezing the movement (so it looks still) or letting the moving object intentionally blur (giving it a sense of movement).

32. To freeze movement in an image you’ll want to choose a faster shutter speed and to let the movement blur you’ll want to choose a slower shutter speed. The actual speeds you should choose will vary depending upon the speed of the subject in your shot and how much you want it to be blurred.

34. Learning the modes

35. Auto mode This is the automatic mode found in all cameras. It is used by beginners and professionals who just want to take a quick snap without worrying about exposure settings. In the automatic mode, you will usually not be able to adjust ISO or white balance settings.

36. Shutter Priority Mode The Shutter Priority Mode is best used when you're taking fast action photos and is usually found in enthusiast or advanced digital cameras. Here, you select the shutter speed and the camera chooses the best aperture. Some examples would include sports or wildlife photography, where you’ll need a high shutter speed. SEEN AS S or TVenthusiastadvanced

37. Aperture Priority Mode – AV or A The Aperture Priority mode is found in many enthusiast level cameras, such as the Kodak EasyShare DX7590, Panasonic Lumix DMC-FZ20 or the Canon PowerShot G6. Essentially, what happens here is that you select the aperture, thereby locking your depth of field. The camera then automatically sets the best shutter speed to match the conditions. When do you use the the Aperture Priority mode? Well, its very suitable when you're shooting a stationary subject when you want to control your depth of field and aren’t too concerned about shutter speed.Kodak EasyShare DX7590Panasonic Lumix DMC-FZ20Canon PowerShot G6

38. Manual Mode - M In this camera mode, anything goes. You can set the shutter speed and aperture, with options to change white balance, ISO, flash and even focus on some cameras. Choose this mode if you know what you're doing and want maximum flexibility for experimenting with the photo.

39. Landscape Mode As the name implies, the Landscape mode allows you to shoot pictures of landscapes like mountains, Your camera will select the smallest aperture possible under the conditions to maximize depth of field in the image. Note that the Landscape mode may not always work.

40. Portrait Mode If you want to shoot close-ups of people or faces, the Portrait Mode is the mode to choose. When you choose Portrait mode, the camera will select a wide aperture setting, minimizing your depth of field for a soft background effect, and also may adjust your zoom. In addition, the flash setting will try to switch to red-eye reduction.

41. Macro Mode If you take pictures of flowers a lot, this mode is invaluable. The Macro Mode allows you to focus on objects at amazingly small distances - sometimes just centimeters from the lens. Use the Macro mode when you need to capture the smallest little details on your subject.

42. Sports Mode If you want to capture fast action, then you'll need the fast shutter speed setting offered by the Sports Mode. When you switch to this mode, your camera will automatically choose the fastest shutter speed possible given the situation. Some cameras will also activate continuous shooting (instead of single frame), enable the evaluative metering mode (if any) and also disable the flash.

43. When to use Aperture Mode - If you want a shallow DOF (for example in the shot to the right which has the flower in focus but the background nice and blurred) they’ll select a large aperture (for example f/1.4 - as in the example to the right) and let the camera choose an appropriate shutter speed.

44. When to use Aperture mode - If they wanted an image with everything in focus they’d pick a smaller aperture (for example f/22) and let the camera choose an appropriate shutter speed (generally a longer one).

45. When to use Shutter priority mode - most people switch to shutter priority mode when they want more control over how to photograph a moving subject.

46. When to use Shutter priority - For example if they want to photograph a racing car but want to completely freeze it so there is no motion blur they’d choose a fast shutter speed (say at 1/2000 like in the first shot below) and the camera would take into consideration how much light there was available and set an appropriate aperture. If instead you wanted to photograph the car but have some motion blur to illustrate how fast the car is moving you might like to choose a slower shutter speed (like the second shot below which has a shutter speed of 1/125) and the camera would choose a smaller aperture as a result.