Introduction
Photoshop is a powerful tool. It allows you to import images, crop, rotate, and resize images, and clean them up to bring out colors and sharpen the look of the image. It also allows you to properly save the images so that you can use them in other programs, such as MS Word, MS PowerPoint, and the World Wide Web.
Images can be brought in to your computer via various methods, including digital cameras, the world wide web, email, or scanning directly into your computer via Photoshop, PowerPoint, or other programs. This document will not cover these methods, but rather will look at how to manipulate images within Photoshop.
1. Importing Images
2. Cropping Images
3. Rotating Images
4. Adjusting Images
5. Removing Blemishes
6. Removing Redeye
7. Removing Image Items
8. Resizing Images
9. Saving Images
1. Importing Images
This section is a quick introduction to scanning with Photoshop, not an exhaustive discussion of the various image-capturing methods.
1.1. Open Photoshop.
1.2. Go to File/Import and select your scanner. By doing this you are starting the software that runs your scanner. Each scanner has it’s own software, so be sure to acquaint yourself with the scanner software before proceeding.
1.3. When scanning the image, be sure to import it at a high dots per inch (dpi). For web and PowerPoint presentations, import it at 150 – 300 dpi. For quality printing, 300 – 600 dpi will do. Please note: the larger the dpi, the larger the file.
1.4. Return to Photoshop to adjust the image.
2. Cropping and Rotating Images
Cropping the image can get rid of unnecessary edges of the image, or it can be used to select a portion of the image that you want to use. Cropping can be done two different ways.
2.1. From the Toolbar, select the Rectangle Marquee Tool. See Figure 2.1
2.2. Starting in one corner of the image, draw a box of “marching ants” around the area that you want cropped.
2.3. On the top menu, choose Image/Crop. Now your image is cropped. It is okay to crop numerous times to get the image to look exactly as you want it.
2.4. To deselect the “marching ants,” go to Select/Deselect on the top menu. Alternatively, you can use the keyboard shortcut Ctrl+D.
2.5. If you need to undo this step, or any step in Photoshop, you can go to Edit/Undo. Alternately, you can use the keyboard shortcut by holding down the Ctrl key and pressing the letter Z (Ctrl+Z).
2.6. If you know the specific image size that you want to use when cropping your image, or if you want more cropping abilities, use the Crop Tool on the Tool Palate. See Figure 2.4.
2.7. Once you select this tool, the toolbar at the top of Photoshop will change, allowing you to enter the specific dimensions that you want for cropping the image. When you draw the box of “marching ants,” the remaining image will be shaded
2.8. You can click on any corner and resize the crop area, and you can click and hold the mouse outside of the selected area and rotate the cropped area. This is useful for specific cropped effects.
2.9. To make the crop permanent, hit Enter. To cancel the crop, hit Esc.
3. Rotating Images
Often an image may need to be rotated or flipped. This can all be done from the same menu.
3.1. To rotate an image, go to Image/Rotate Canvas. On that menu, choose the rotate that best fits your needs.
3.2. If you need to alter the image an arbitrary amount, choose Arbitrary. Enter in the amount
you want to rotate the image, and choose CW (Clockwise) or CCW (Counterclockwise).
3.3. Note: If you find that you need to rotate the image more than once, undo the first rotate,
and put in a new rotate angle. Rotating more than necessary will reduce the quality of
your image.
Figure 2.4
Crop Tool
4. Adjusting Images
After the image is cropped and rotated, you may need to alter the color, brightness, and contrast of the image. These instructions are a good introduction to adjusting images, but are by no means an exhaustive look at adjusting methods. As you become more familiar with Photoshop,
experiment with some of the other methods in the Adjustments menu.
4.1. To adjust an image, go to Image/Adjustments. The three main adjustments are Auto Levels, Auto Contrast, and Auto Color. For most situations, these steps (in this order) will properly adjust your picture.
4.2. If you need to further adjust your image, go to Image/Adjustments/Curves… This screen can be difficult to use. Be sure the Preview box is checked. Click on the curve line and drag the line until you like the look of your image. If you don’t like the changes you made, either Cancel the Curves window, or hold down the Alt key, and the Cancel
button will change to a Reset button. Click the Reset button while holding the Alt key.
4.3. If you are altering a number of pictures, and need to select Auto Levels, Auto Contrast, and Auto Color repeatedly, you may want to write an Action that will do this for you. An Action is similar to a Macro in a word processing program. To do this, first make sure the Action window is active. Go to Window/Actions to activate the window, then click on the Create new action button (below). In the popup window, name the Action.
4.4. At this point you are recording a new Action. Proceed with each step that you would like recorded (in this example, go to Image/Adjustments/Auto Levels, Image/Adjustments/Auto Contrast, and Image/Adjustments/Auto Color.) When you have completed the steps you want recorded, stop the Action. The Stop control button, and the Record and Playback buttons, are at the bottom of the Action window, and look similar
to a cassette recorder.
4.5. Once the Action has been recorded, go on to the next picture and hit the Play button on the Action window. All the recorded steps are completed automatically. You can use Actions for various tasks in Photoshop. Experiment with Actions for other tasks and automate your common tasks.
5. Removing Blemishes
Photoshop has some handy tools that allow you to clean up images, and even alter them altogether. This section is an introduction to these concepts and will cover removing spots and marks out of the image.
5.1. The best tool in Photoshop for cleaning up blemishes and error to the image is the Heal tool. It is on the Tool Palate, and it looks like a band-aid. See Figure 5.1.
5.2. On the top toolbar, choose a brush size. Be sure to choose a size big enough to cover the blemish and a bit of the area on either side of the blemish. For the example, I chose a brush size of 8.
5.3. Zoom in on the area of the picture that needs to be touched up. Zoom can be found under the View menu, or you can use the keyboard shortcut keys. Zoom In is Ctrl++ and Zoom Out is Ctrl+-.
5.4. Select a sample area for the Heal brush to use. Do this by holding down the Alt key and clicking on an area of the picture that closely matches the blemished area.
5.5. Hold down the left mouse button and trace the line of the blemish. A + symbol will show the sampled area as you cover the blemish
The repaired blemish may be slightly off color while you are tracing the line of blemish . This will be repaired when you let go of the mouse button. Notice how the pattern and shading on the repaired portion of the line perfectly match the area surrounding it.
5.6. This tool is very powerful, and it may take some experimenting to understand it. Try sampling from different areas, and pay attention so that your sampling route does not cross the area you are trying to repair. Also pay attention to repairing a blemish too close to a drastic color change, as the computer might not interpret your intentions accurately,
and may blend too much of an undesired color or shading
6. Removing Redeye
Redeye can be distracting in an image, but it can easily be cleaned up following these steps.
6.1. Enlarge the eye by Zooming In (Ctrl++ or View/Zoom In) on the eye.
6.2. Use the elliptical tool to make a circle or oval around the red eye. To find the elliptical tool, hold the mouse button down on the marquee tool (figure 2.1) and select the elliptical tool.
6.3. On the main menu, choose Select/Feather, and set it to 1 or 2 pixels. This helps to make a smooth transition from iris to pupil.
6.4. On the main menu, choose Image/Adjust, then Hue/Saturation.
6.5. Make sure the preview box is checked, and then choose Colorize.
6.6. Either leave the Saturation at the Colorized level, or reduce it to 0 if necessary (this will make the eye look grayscale). Click OK.
6.7. On the main menu, choose Image/Adjust, then Brightness/Contrast.
6.8. Reduce Brightness to –10 to help blend the changes. Click Ok. Do the other eye, if necessary.
6.9. Note: These steps can be made into an Action (steps 4.3 – 4.5) to be used repeatedly. If you make a Redeye Action, only record steps 6.3 through 6.8. Steps 6.1 and 6.2 will need to be completed on each eye before running the Redeye Action.
7. Removing Image Items
Removing unwanted items from an image is tricky, but with a little experimenting and practice, it can be accomplished.
7.1. In the following picture, I will remove the table to the left of the nurse.
First, select the Clone Stamp Tool from the Tool Palate. See figure 7.1.
7.2. On the top toolbar, choose a brush size. Be sure to choose a size big enough to cover a lot of area, but small enough to have some control over the cloning. For the example, I chose a brush size of 10.
7.3. Zoom in on the area of the picture that needs to be touched up. Zoom can be found under the View menu, or you can use the keyboard shortcut keys. Zoom In is Ctrl++ and Zoom Out is Ctrl+-.
7.4. Select a sample area for the Clone Stamp brush to use. Do this by holding down the Alt key and clicking on an area of the picture that closely matches the area you want to clone.
7.5. Hold down the left mouse button and begin cloning. A + symbol will show the sampled area as you work. Work away from your sampled area, so that you don’t accidentally sample the area you want cloned. Sample new areas often to avoid this mistake.
7.6. Note the slight discoloring in the left example (above). When the table is completely removed, use the Heal tool (Step 5) to blend the colors accordingly. Make smaller strokes with the Heal tool for the best blending (see right example, above). When you are finished you should have a table-free image. As you work with the Clone Stamp and Heal tools more, you will find that you can alter more advanced pictures.
8. Resizing Images
When you have completed manipulating the image, you may need to resize it for the final product.
8.1. Go to Image/Image Size. In that window, be sure the Constrain Proportions box is checked.
8.2. A chain link image will be visible to show the Constrain Proportions box is checked.
8.3. For computer screen image, set the Resolution to 72 pixels/inch (also referred to as dots per inch, or dpi). This is all that a computer screen can display. If the file is larger than 72 dpi, the file size will be larger, but the quality will not be. (Note: if the image will be used for printing, you will want a bigger dpi. 150-300 dpi is often used for printing. If printing professionally, check with the printer regarding their specific requirements.)
8.4. Set the Width to the size you want. For PowerPoint images, anywhere between 350-450 pixels is fine. If the file is taller than it is wide, set the Height to 350-450 pixels.
8.5. Verify that the dimensions are set to pixels. Anything else will give you a much larger file size than you were expecting.
8.6. Click OK.
9. Saving Images
It is important to save the image at the end, as well as any time you make major changes. Saving can seem like a nuisance, but it will prevent a lot of frustration if you save regularly.
9.1. This step is entirely optional. Before saving an image, you may want to sharpen it to bring out more detail. To sharpen an image, select Filter/Sharpen/Unsharp Mask. This will increase the focus of the image. If you don’t like the effect, you can undo the change (Ctrl+Z, step 2.5) Be sure to only sharpen the image once. Doing it too many times will
result in a loss of image quality.
9.2. Saving a file in Photoshop is similar to other Windows programs. Go to File/Save or use Ctrl+S from the keyboard to save. Photoshop can save images in many formats, and will attempt to choose the format best suited for the image being saved. If you want to change the file type, just use the pull down menu and select the file type you are looking for.
9.3. The main format that Photoshop uses is psd. This format saves all the Photoshop setting precisely as you used them, so further modifying the image is possible. Saving files in this format makes for very large files that can only be read by Photoshop. This is fine for
master copies of the files, but not so good for using the files in other programs.
9.4. When saving images for use in other programs, or to email to somebody, you should save them in a user-friendly and smaller file type. Both gif and jpg are perfect file formats for computer-based images. Use .jpg for images that are photographs or similar
picture types. Use .gif for images that are drawings, graphs, and other line art.
9.5. When saving a jpg, you will see a JPEG Options box. The main settings here are Quality and Format Options. When setting the Quality, keep in mind that the larger the quality, the larger the image file. Usually a quality of 4 is good enough for a computer graphic. Make sure the Preview box is checked, and you can see the quality difference, especially in the lower quality values. Under Format Options, select Baseline (“Standard”).
9.6. When saving a .gif, you may be asked if you want to flatten layers. If you intend to save the file as a .gif, say yes. If you don’t receive this message, that is okay. The next box you will see is Indexed Color. The main setting to be concerned with in this box is the number of colors. You can choose between 2 and 256 colors. The less colors you use,
the grainer your image will look, and the smaller your image file will be. Be sure the Preview box is checked, and you will see the quality difference. If you are unsure how many colors to use, leave it at 256. The next box will be GIF options. Choose a Row Order of Normal and say OK.
9.7. Another save option is File/Save for Web. This saving option allows you to save as a gif or a jpg, but with more saving options and attention to detail. In many situations, this can help make an even smaller file size as well. It will also save your settings for the next time you Save for Web. Feel free to experiment with this feature to try and find the best
way to save a file.
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