Name Digital Imaging I Chapters 9 12 Review Material Chapter 9 Filters A filter is a glass or plastic lens attachment that you put on the front of your lens to protect the lens or alter the image as you take it. A lens hood is not considered to be a filter but it is attached to the front of the lens to protest the lens from unwanted light rays and from being scratched or damaged. Filters can be used in the digital world even though there are digital filters that can be applied in apps like Adobe Photoshop. A graduated filter can be used to bring the exposure levels into the normal range when there are real lighting challenges. The use of filters allows you to change and image or correct an image when it is taken and not to have to rely on the computer to make the changes. The use of filters allows the photographer to improve their craft when taking images. An excellent type of filter to use is the circular polarizing filter that can be used to cut glare and reflections and also to darken blue sky and enhance colors in an image. To use slower shutter speeds in bright light use a ND (Neutral Density) filter. When shooting with very small f stops like f22 you can get a diffraction pattern like a star filter when light passes through the small aperture opening in the lens. Digital sensors do not naturally see infrared light since they have a filter on them to prevent that type of light from being seen. Filters allow you to control tones and colors on the camera and not have to wait for the use of the computer later. The two types of filters that are most useful to the digital photographer of today are the circular polarizer and the UV (Ultra Violet) filter. The UV filter is used to protect the lens from being scratched and keep ultra violet light from altering the image. The first reasons for using filters in the digital age are: 1. Filters bring extremes into range, 2. No computers are needed to alter the image, 3. Less work for the photographer, 4. You see what you are getting when you take the image, and 5. The use of filters encouraged the attitude of craft in the photographer. The top four reasons for using a polarizing filter are: 1. Darkens blue sky, 2. To remove reflections, 3. To enrich colors by removing unwanted glare, and 4. Cut through haze. The reason you do not want to always keep a polarizing filter on your lens is because if reduces exposure and make the scene much darker on a D SLR. This type of filter also cost much more than a UV filter that is used for protecting the lens. A Graduated or Split ND filter is called that because it is dark on part of the filter and clear on the other part. In working with filters remember that most filters require additional exposure and they can sometimes give false readings with your camera meter. The use of filters can help you create fun and interesting images.
Chapter 10 Composition In the early days of photography the photographers were more concerned with simply getting an image than with the art of composition. As a photographer you are to make a photograph not just sight on a target. Better composition comes from the right attitude toward taking a picture. With digital imaging there are two ways to use your LCD to help improve your photographic composition, live LCD or LCD review. As a photographer do not try to copy a scene. You want to grab and hold the viewer s eye with your photographs. Use the rule of thirds to create off center placement of your subjects in the images you take. Here is what the rule of thirds look like: Put center of interest at this point. The rule of thirds can also help you position the horizon and other strong horizontal or vertical lines in an image in an off center manner. You can separate your subject from the background by using a shallow depth of field which you can get by using a very large lens opening like f1.8 or f2.0. Another way to separate your subject from the background is to make sure the background is lighter or darker than your subject. You can also create a better composition in an image by using a different angle on the subject. A wide angle lens can be used to create a great depth of field when using a small aperture like f16 or f22 and a telephoto lens can be used to create a shallow depth of field by using a large aperture like f1.8 or f2.0. Photographic composition is made up of a set of guidelines and not rule that you as a photographer can follow but do not have to follow. If you like an image simply take it. As a photographer you need to train your eye to look at all parts of the image not just the subject. Mergers are items that come out of your subject that do not belong or parts of items that are cutoff in an image that make the image look incomplete. A famous American photographer that was concerned with composition was Ansel Adams. The device on your digital camera that helps you to better compose images is your LCD. You can use the following the draw the viewers attention to the subject of your images: 1. Uncommon angles, 2. Unusual subjects, 3. Dramatic light, and 4. A clearly seen subject. You can use lines, colors and lighting to direct the eyes of your viewer to your subject. The best lens to use in isolating your subject is the telephoto lens. Use the wide angle lens to show a great deal of a scene and make your subject look rather small in relation to the area around it. You can use an arch, window, tree branch or any object you shoot through to create a frame for an image. A dark frame can add drama to an image.
Including less in an image is better than trying to include too much in the scene. Trying to include only what you must include in an image to get the point across is using the composition guideline of simplicity. Composition is what attracts a viewer to your photo, helps them see new things in subjects you have captured and is what helps them say, Wow! What a great photograph! To get a good image you must find the photography in the scene. When a photograph has a strong center of interest, it grabs the viewer s attention and makes the image easier to understand. You can direct attention to your center of interest by the use of light as well as what supporting elements are in your photograph. The key to a great photograph is looking for colors that are different in the subject and the background. Use depth of field to make the subject sharp and everything else soft in the focus. There is great value in keeping the composition simple in an image. Another term you will often hear about composition related to simplicity is unit. This means that everything in the photograph belongs in that picture. A simple an effective technique for defining a composition and giving it visual interest is to frame the subject in some way. An out of focus frame can create depth in an image. Photographers that are not concerned with photographic composition are called snap shooters by the author of the Kodak book. Two methods that can be used to create a relationship between the subject in an image and the rest of the components in that image is using the Rule of thirds and having a strong Center of Interest. To create a strong center of interest in any image be sure that the subject of the image is clear and remove any other completing elements in the image. Six ways to isolate the subject is any image are: 1. Brightness contrast, 2. Color contrast, 3. Sharpness contrast, 4. Use of a telephoto lens, 5. Use of a wide angle lens, and 6. Trying to separate the subject from the background. Two problem areas with photographic composition are the edge of the image and the background. The key question to ask about any image you take is: What is that image about? You can create a frame for any image by looking for an item in the foreground that you can use to frame the center of interest. Chapter 11 Shooting Action A still image photograph can represent or interpret movement, but it cannot actually show it. In the early days of photography action was difficult to capture because of the slow lenses and shutters and low ISO settings. There are three ways to interpret action with still photography: 1. Stopping or freezing it, 2. Blurring it, or 3. Using a combination of both with panning. The closer you are to the action the harder it is to stop the action. Faster moving subjects will require a faster shutter speed to stop the action.
Action coming towards you or away from you is easier to stop than when the action is moving across your view or diagonally towards you. Stopping action depends on the shutter speed you use, how close you are to the action and the speed of the subject. In order to get great action shots in sports you need to know the sport. One of the biggest problems with action shots in the early days of digital photography was shutter lag, where it takes the camera a long time to take the image after you press the shutter release button. To get a great action shot you must learn to anticipate the peak action in the sport. Autofocus can be a real problem with action photography. To get the best action shots with a D SLR set the camera on continuous mode with the alservo focusing where the camera is always focusing on the moving subject. There is an action mode setting on most D SLR cameras that looks like a runner. When this mode is selected it will set the shutter speed at a higher speed and also increase the ISO. On many D SLR cameras it also allows you to take shots more quickly. The faster the shutter speed the easier it is to freeze action (stop) like using a shutter speed of 1/500 th or faster and the slower the shutter speed the more blur you will get in an image, like a shutter speed of 1/30 th. Being able to stop the action does depend on the type of action it is, how close you are to the action and the angle of the movement of the action. In using the panning technique to get a blurred background but a clear moving subject you want to set the shutter speed at 1/30 th. Using a tripod may also help in the panning technique. To get great fireworks images you will want to use a small aperture and set the shutter speed on Bulb to allow for multiple bursts to be recorded. The greatest area of photography that using the ability to stop or freeze action would be sports images. Most sports action shots can be stopped at 1/500 th for a shutter speed. Use a slower shutter speed like 1/30 th to blur actions shots. Images taken during the day are easier to stop since you have daylight for the lighting. Autofocus can be a problem with action images so you might want to set your D SLR on manual focus and just focus on a spot where you think the action will take place. The most common method used to take action images is to use a fast shutter speed combined with a high ISO like 800 6400 to stop the action. High speed action shots allow the viewer to see things they cannot see with the unaided eye. A key element to any action photography is timing, being able to get the shot at just the right time for peak action. With the panning technique you can get a sharp subject with a blurred background that helps place emphasis on the moving subject. The main advantage the digital photographer has over the film photographer when it comes to taking action images is the fact that cameras today have much faster shutters, higher ISO setting and the LCD to see what you have taken a picture of right after you take the image.
When taking action images be sure to experiment with different lenses, ISO settings, shutter speeds, take plenty of images, and try different angles on the action. Five tips to help with the AF (Auto Focus) on using the D SLR to take action shots are: 1. Start your focus early, 2. Use continuous AF settings, 3. Know your camera, 4. Anticipate action for AF, and 5. Turn off the AF when needed and just focus on a spot. When you use the action mode on a D SLR you will get better action images since the camera will automatically increase the shutter speed and ISO settings for you to match sports settings. With panning, be sure to use a slower shutter speed, usually about 1/30 th of a second and move in the direction of the action and take an image then follow through. You can find action images just about anywhere not just in the area of sports. Chapter 12 Close up and Macro Photography Early cameras could not focus up close. Parallax gets worse the closer you are to your subject. This is only true of digital cameras that are not D SLR cameras where you see the subject in the LCD or viewfinder through picture taking lens. Clouse up images have impact. Kodak research shows that most people do not take images that are closer than 6 10 feet from the camera. Camera movement and subject movement can be a real problem with close up or macro photography because you are usually using large lens openings with slower shutter speeds. The tripod will be a great help in taking close up or macro images. With a close focusing lens you will get the best results when you use f stops of f8 f11 since most lenses take the best images at those apertures. You can get close up filters that can be attached to the front of your lens to allow you to focus more closely on any subject. There are flash units that are made especially for close up or macro photography. At very close up or macro focusing you will have a real problem with depth of field. Focus is usually a real challenge because of the very large lens openings like f1.8 or f2.0 which will give a very shallow DOF in any image. Autofocus can be a real problem with close up or macro photography. You may want to use manual focus when taking these types of images. You will get better close up and macro images if you use a contrasting background for your subjects. The D SLR has made close up photography easier for everyone. Images that are only 2 3 feet from your camera are considered to be close up images. Images that are inches from your camera lens are considered to be macro type images. Usually macro images are life size or a 1:1 ratio. Macro lenses will offer better close up images than close up filters that attach to the front of your regular lens. If you do not have a macro lens you can use a telephoto lens to get closer to your subjects. A good ISO to use for close up or macro photography is 800 ISO. Too high an ISO will produce noise in a close up or macro image. D SLR cameras with folding or tilting LCD screens make taking close up and macro images easier.
Lenses designed to take images at a 1:1 or 1:2 ratio are called macro lenses. Two problems found in early cameras that made taking close up or macro images impossible were the lack of close focusing lenses and the problem of parallax. The D SLR is so great for close up work because you can see in the LCD or viewfinder exactly what the lens sees before you take the image. Close up photography is possible with most digital cameras at any time and for any type of subject. Using your flash with close up photography will allow you to use faster shutter speeds and smaller f stop so that you can get a better DOF and sharper images. One problem with using the flash with close up and macro images would be flash burn because the flash is so close to the subject. You might want to put something between your flash and the subject or bounce the flash unit. You can preview the DOF with most D SLR cameras before you take the close up image. Much of your close up or macro photography will be experimental. Have fun taking images of objects using close up photography. Three ways to improve the focus when taking close up or macro images would be: o Know what is important in the image o Use manual focus o Move the camera to get it into focus Seven ideas that will help with your close up or macro photography are: o Use a higher ISO setting o Use a tripod o Shoot multiple shots with the continuous shooting settings o Watch the plane of focus o Use a flash o Try a special close up lens o Use mid range f stops like f8 f11