Technology Learning Activity: Multimedia CIMC. Student Edition TE8135

Transcription

1 IMC Technology Learning Activity: Multimedia Student Edition CIMC TE8135

2 Technology Learning Activity This TLA covers information on digital imaging sources and uses, photography guidelines and tips, and more. Photos and digital images are a big part of multimedia projects. They can capture attention, provide interest, and convey messages. Learning the basics of good photography will help you create better multimedia products. What You Will Learn About: sources of digital imaging elements of good photographs digital camera technology parts of a camera factors that affect quality imaging design principles related to using digital images acquiring images editing images converting images from one format to another using images in presentations 7

3 Digital imaging can best be described as creating digital images from either physical or analog objects. Most digital images are created through the use of digital cameras or from scanners that take physical items and digitize them. However, there are many sources of digital imaging that do not require physical imaging at all, but come from complex processing of non-image data. Let s look at some sources you might use for digital images: Digital Camera used to take photographs in digital form that can be transferred directly to personal computer and edited. Scanner used to transform physical sources of images and/ or text into digital sources that can then be edited with a personal computer. Clip Art or Photo CD prepackaged artwork, photos, and graphic representations can often be purchased on compact discs or come as part of other software purchases such as image editing software or operating systems. Video video from camcorders, digital video streams, and other sources of video can be used to create still images that can be edited and used in multimedia production. Internet there are literally millions of images on the Internet that are already in digital format. Many of those images can be used for development purposes, especially educational purposes. Remember, however, that you need permission to use Internet materials just as you would to use hard copy materials. Photography Photos will probably be a big part of any multimedia presentation you create, whether it is a simple presentation or a complicated interactive web site. Sometimes they are picture of real things you want to show, other times they are backgrounds, and still others are used to illustrate a concept or process. No matter what you use photos for, learning about digital imaging and the basic principles of photography will help you create interesting images. 8

4 Elements of Good Photographs Words to Know composition the arrangement of the objects in a photo focal point main subject of the photo Rule of Thirds guideline for composition; studies show the brain prefers images where the subject is slightly off center; this guide lays out a grid to help with composition Photos preserve memories great friends, great places and great times and illustrate thoughts, emotions, and more. Throughout the world, thousands of photographers take billions of photos of everyday events and special subjects. Are they all good photos? Absolutely not! In fact, only a tiny percentage of those photos are good. So, what characteristics do the good photos share? A good photo is in focus the image is clear and sharp. Out-offocus photos look unprofessional. By focusing the camera correctly and by holding the camera steady while pushing the release button to take the photo, you can get a good, focused shot. A good photo is well composed. The subject, also known as the focal point, should attract attention. Composition describes the arrangement of objects in the photo. In a well-composed photo, the subject will fill the frame so the photo does not have empty, useless space. Good photographs will have simple, uncluttered backgrounds when possible. Taking the photo from an unusual angle may also improve the fi nal product. A helpful concept for improving composition is the Rule of Thirds. According to this guideline, the brain prefers photos in which the subject is slightly off-center. Therefore, the photographer should position the subject inside the edge of the frame by approximately one-third. If the frame is divided into thirds both horizontally and vertically (imagine a tic-tac-toe grid, [see next page]), the points where the lines intersect are good positions for the subject of the photo. The photographer should avoid placing the subject in the exact center, at the very top or bottom, or in the corner. By using the Rule of Thirds, a beginning photographer can learn to create nicely balanced pictures. 9

5 WEB ACTIVITY Go to com/photographytips/composition. htm and read the information on composition. Write definitions for the following terms: simplicity framing texture leading lines colors 10

6 A good photo will have proper exposure and lighting. Exposure is the amount of light entering the camera lens; it is determined by the size of the lens opening and the length of time the light is allowed through the lens. Proper exposure ensures the photos are neither too light nor too dark. In some cases, this will mean using a flash, which usually provides front lighting. Lighting refers to the direction of the light in relation to the photo s subject. Other options are back lighting (creating a silhouette), side lighting, or top lighting for varying effects. too dark too light just right Go to photographytips/exposurebasics.htm and read about the exposure. Then read about lighting at picturecorrect.com/photographytips/light.htm. What were the main things you learned from reading this information? 11 WEB ACTIVITY

7 The subject or event being photographed should be interesting or express your message. Good photos can also suggest emotion through their content, and they provide information for those who see them. What message do you think the photographs below are trying to express? WEB ACTIVITY Go to eknec/pagequerier.jhtml?pqpath=317/10032&pq-locale=en_us List the ten tips Kodak gives for good photos below. 12

8 Challenge Activity Photography tips and tricks Go to and scroll down to the Advanced Tips section. Select one of the areas listed and read the information for that tip. Summarize the information you read. 13

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10 Digital Camera Technology How long have digital cameras been around? Probably longer than you think! An electrical engineer working for the Eastman Kodak Company created the fi rst digital camera in He probably had no idea what impact his creation would have! It caused a revolution in the photo industry. While both film and digital cameras use light to create photographs, digital cameras save the image as pixels, picture elements that are the tiny squares of a digital photo. Memory cards, rather than film, record the images. Digital cameras are classified by how many pixels the camera records in a square inch, which is known as resolution. The higher the resolution, the more pixels the camera records per inch, the crisper the image can be, and the more it can be enlarged. You should shoot at a high enough resolution that your photos are sharp and clear for your intended use. Resolution is typically expressed as pixels per inch (ppi) or dots per inch (dpi). Magazines require photos with higher dpi counts than newspapers, and newspapers require higher counts than Web publications. Higher dpi counts result in larger image files, though, which require more storage space. Here are some basic guidelines for dpi: Magazines 300 dpi Newspapers 150 dpi Computer/web-based applications 72 dpi Parts of a Camera All film and digital cameras share some of the same basic parts: A glass or plastic lens captures an image by gathering light and focusing a subject. A diaphragm creates the opening, or the aperture, that controls how much light enters the camera through the lens. A lower aperture number like f4 allows more light to enter and produces softer background images. This is considered low depth-of-field. In other words, the field of focus is more narrow. Using a higher aperture number like f16 results in a sharper background or higher depthof-field. See the diagram on the next page. 15

11 More Light Entering the Sensor Less f/2.8 f/5.6 f/8 f/11 f/16 f/22 Softer Background Images Sharper Background Images A camera s shutter also controls how much light enters the camera by adjusting the length of time the shutter remains open as the photo is taken. A body provides the light-proof housing for the camera. A viewfinder can be either through a frame or a lens that allows the photographer to see the subject of the photograph to be taken. Digital cameras usually have a video screen to see the image before it is taken and to review the image after it is recorded. Just as with film cameras, digital cameras come in two basic types: point-n-shoot and single lens reflex (SLR). A point-n-shoot camera is the simplest way to capture a photograph. This type of camera has a built-in lens, fi xed aperture, and automatic flash, which it uses automatically to determine the correct exposure and focus as it records the image. More advanced versions have specialty settings to allow the user to take close-up photos using the macro setting, for example. Many also allow the photographer to zoom in one of two ways, optically and digitally. Optical zoom is superior to digital zoom because it allows the photographer to maintain picture quality. When using an optical zoom, the photographer adjusts the lens to magnify or expand the area in the picture, but the resolution (number of pixels) and, therefore, the picture quality, remain the same. The range of the optical zoom is indicated by a magnifi cation number such as 3X or 4X. 16

12 Digital zoom enlarges the subject by magnifying the center of a picture. As a result, the center of the picture appears larger, but image quality is reduced. Through digital zoom software, the camera adds pixels to create the larger image. In effect, it crops, or edits, the picture while it is still in the camera and reduces the picture s resolution. A digital zoom adds convenience, but it limits the ability to enlarge a picture because of the lower image resolution. If available, optical zoom is the best option to use. An SLR camera (so named because the same lens is used to view and take the photo) has interchangeable lenses (normal, close-up, telephoto or zoom, wide angle, etc.) and allows more control over the image. To take full advantage of either camera type, you should review the owner s manual before taking any photographs. WEB ACTIVITY Go to pub/a/mac/2002/10/22/digi_photo_ tips.html and read about some practical tips for getting good digital photos. Which tip did you find the most helpful? Why? 17

13 Factors that Affect Quality Imaging There are many factors that affect quality imaging; however, some are more important than others. Digital imaging is a two-part process. The fi rst part is to actually acquire the image. Without a decent image, no amount of editing will create a good image! However, editing can greatly enhance good images. In fact, many multimedia professionals work exclusively with image enhancement and correction. Image enhancement and correction can be used for anything from developing a better fashion photo to picking out very minute details from a satellite image. These can be very complicated operations. However, some of the basic factors that affect digital imaging quality are listed below. Factors Affected by Image Source Sharpness affects the amount of detail an image can display Noise is shown by the variations in image density from light sources and pixel variations in digital images Dynamic range the range of light levels that a camera can capture Color accuracy accuracy is most affected by camera quality and the camera s ability to filter color Color gamut the range of colors that a camera can reproduce either in hard copy photos or digital format Factors Affected by Editing Contrast the comparison of color in an image, usually defi ned by lighter and darker shades Color balance the adjustment of the amount of red, green, and blue primary colors in an image. Color balance can be used to control the mixture of color and to correct images in editing. Color saturation refers to the intensity of specifi c color tones and the way they are distributed within an image. Resolution most affected in digital imaging by dpi (dots per square inch) values. DPI refers to the number of digital color dots make up certain portions of an image. 18

14 WEB ACTIVITY Visit the Cornell Library s online digital imaging tutorial at cornell.edu/preservation/tutorial/ contents.html. Read the contents of the tutorial, and then answer the questions listed below. 1. What information from the tutorial did you find most useful to you in your multimedia studies to this point? 2. What did you find most informative about Quality Control? Design Principles Related to Using Digital Images Using appropriate digital images to design good multimedia presentations is one of the most common tasks for multimedia designers. However, simply dropping graphics into a presentation doesn t mean they will help or enhance your presentation. You will need to use sound design principles to create a good presentation. Uses for photos and graphics include: To support copy points many visuals in multimedia presentations (especially business and educational presentations) are used to support textual points or speaking points from the presenter. To provide visuals for clear understanding one of the most basic visual uses for graphics in presentations is to simply provide a clearer picture of the topic for viewers. To maintain visual interest and attention visual presentation elements help to both maintain audience interest and attention. Stimulating and informative graphics help to build trust within your audience and keep them focused on your presentation. 19

15 To display complex concepts sometimes words are a difficult way to explain in-depth ideas. Have you ever heard a picture is worth an thousand words? In the case of multimedia presentations this saying can be true! Complicated thought processes or activities can often be summarized with graphics, making extended explanation unnecessary. To diagram processes like complex concepts, complicated processes are also often better displayed through graphic representation. Your audience will not be required to keep details in short-term memory, and you will be able to graphically display the process that you have already thought out. To display statistics and charts statistical representations of data such as charts and graphs can help you to display information from hard data sets. Such data is not easily represented through text or speech. To create background or supporting graphic color not every graphic needs to have an educational purpose for your audience. Some graphics are simply used to create an atmosphere for you presentation or to make it look more professional. WEB ACTIVITY Explore the Visibone Webmaster s color palette at colorlab/. With your instructor s help, identify the numbers that go with each color on the color palette. What is their function? 20

16 Activity 1 Acquiring digital images What You Will Do: For this activity, you will acquire digital images from a scanner, digital camera, and the Internet. You will use three sources to get these digital images a scanner, a camera, and the Internet. What You Will Need: digital camera computer with internet access photo, logo, drawing or other artwork that can be scanned What to Do: 1. Use a scanner to capture a digital image and store it on your personal computer. 2. Use a digital camera to take photographs and store them on your personal computer. 3. Save various images to your personal computer from the Internet. Note: Save the images in a location that will be easy to find as you will use these images in another activity. 21 scanner

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18 Image Editing Editing images can be a time consuming process. But professional multimedia designers do not take this process lightly. Editing your images is one of the most important things you can do to present a professional-looking presentation. While there are many complex software techniques that can be used for image editing, most fall into several basic categories of image editing. Consult the descriptions of those categories below. To support copy points many visuals in multimedia presentations (especially business and educational presentations) are used to support textual points or speaking points from the presenter. Brightness and Contrast Editing editing for brightness and contrast can help you improve the quality of your image by defi ning the image s shine and by contrasting light and dark colors to create the overall look. Most image editing software has features for controlling both brightness and contrast. Color Balance Editing as described before, color balance is often affected by the primary colors such as blue or red and is often the product of the original image or photograph. Color imbalances can usually be corrected by adjusting the color tone of the image. Contrast Correction sometimes you may need to edit contrast in just a portion of an image instead of the entire image. Editing contrast in portions of an image can bring out important details or de-emphasize unimportant portions of the image that may be distracting. Usually, partial contrast adjustment is done by selecting an area of a digital image and then adjusting the contrast for that area as needed. Crop Editing sometimes you may want to focus on a particular section of an existing image and get rid of the rest. Crop imaging is designed to do just that. Using image editing software, you will be able to select only a portion of the image you have. Then you will crop the image, by deleting the rest of the image from your file. Sharpening usually the last step in the editing process, sharpening can be used to increase contrast around objects in your image. Sharpening helps to improve the overall presence of objects in your images by adding to the contrast of pixels bordering large objects in your image. 23

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20 What You Will Do: Activity 2 Edit a digital image For this activity, you use image editing software to edit one of the images you saved. You will go through several steps to enhance your image and make it even better than before! What You Will Need: computer Adobe Photoshop Elements or Photoshop, Paint Shop Pro or similar image editing software digital images to edit What to Do: 1. With the help of your instructor, open the digital image editing software on your computer. 2. Open a digital image file for editing. 3. Adjust the brightness and contrast levels of the image to their optimum balance. 4. Adjust the image s color balance to enhance the image. 5. Select a portion of the image and adjust the contrast within that area to show more detail. 6. Crop the image to focus on the most important features. 7. Use sharpening to enhance prominent objects within the image. 25

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22 Digital Image Formats There are several different formats for digital images and photos. They have different uses and characteristics. Let s look at them now. jpg (sometimes called JPEG) JPG is the most common image format, and is compatible with more programs and computers than any other format. JPG files are best used for photographs with many colors. JPG files do very well when compressed to save disk space and graphics programs like Photoshop will allow you to view quality and file size relative to compression, so that you can choose the best balance between the two. gif GIF files are widely used on the internet as graphics and icons because they can perfectly render images with 256 colors or less and are relatively small files. However, you should not use GIF files for photographs because most photographs do not do well with a 256 color limit. bmp (bitmap) BMP is an old format invented by Microsoft. Avoid BMP files if possible. They are constrained by color options and are generally HUGE files with no practical purpose. If you must use a BMP file, you should attempt to convert it to another format. 27 tif TIFF files are usually used when the best possible quality is required. However, TIFF file sizes are huge when compared to even the highest quality JPG settings. TIFF files are valuable because they do not lose data through repeated editing and saving whereas over time a JPG image will become noticeably degrading by this process.

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24 Activity 3 Convert graphic file formats What You Will Do: For this activity, you will save images in different file formats. What You Will Need: computer with internet access Adobe Photoshop Elements or Photoshop, Paint Shop Pro or similar image editing software digital images to convert What to Do: 1. Review the following file formats. Ask your instructor for further clarifi cation on file formats. 2. Open your digital imaging software. 3. Open a jpg image. Use your image editing software to convert the file to another format. 4. Open a tif image. Use your image editing software to convert the file to another format. 5. Open a gif file. Use your image editing software to convert the file to another format. 6. Open a bmp file. Use your image editing software to convert the file to another format. 29

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26 What You Will Do: Activity 4 Use digital images Now that we have discussed digital files and digital file editing, it s time to practice inserting simple image files into a presentation. Follow the procedures below, with the help of your instructor, to use digital images in producing simple multimedia presentation slides. What You Will Need: computer with internet access Adobe Photoshop Elements or Photoshop, Paint Shop Pro or similar image editing software PowerPoint, Microsoft Publisher or Word, or another software to make slides, brochures, or posters a variety of digital images What to Do: 1. Open your digital image editing software. 2. If you have not saved edited images from the previous activities, fi nd and edit images to your instructor s satisfaction. Save the images to the proper directory on your computer s hard disk. 3. Convert all files, using the process described in Activity 3, to jpg format. 4. Choose one of the following items to make with your images: A simple PowerPoint presentation of fi ve slides in length A simple poster A simple brochure or handout 31

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28 Review/Quiz and Photography Instructions: Answer the questions by filling in the circle beside the best possible answer. 1. Composition is a. the main part of the photo b. guideline for shooting photos c. the arrangement of objects in a photo d. supposed to allow for a lot of empty space around a subject 2. True or false? Of the thousands of photos taken, most are really good photos. a. true b. false 3. True or false? You should place your subject in the exact middle of your photo. a. true b. false 4. Exposure is a. the direction of the light in relation to the subject b. only determined by the lens opening c. the amount of light entering the lens d. not very important because you can change it later 5. Digital cameras save the image as a. RAM b. tiny circles or paxels c. memory cards d. picture elements that are tiny squares or pixels 6. Resolution is expressed as a. pixels per inch b. dots per inch c. meter range d. both A and B 33

29 7. What does a lens do? a. gathers light b. reflects light c. focuses a subject d. both A and C 8. Dynamic range refers to what? a. contrast range in a photo b. the range of light levels that can be captured by a camera c. the range of sharpness that can be displayed by a video card d. sharpness range in a photo 9. Images are a good way to explain complex processes because a. in-depth processes are often difficult to explain with words b. complex processes don t need textual attention c. presentations can become too long without them d. visual images can t portray simple processes 10. Partial contrast editing does what? a. brightens the entire image b. darkens the entire image c. brings out important details in portions of an image d. adjusts pixels around prominent objects in an image 34