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Adobe Photoshop CS3 |
| Changing Image Size |
If you are working with a pre-existing image you may want to change the Image
Size or Resolution to restrict the file size or dimensions.
Go to Image > Image Size... and a window will appear:
Resolution should always be set to 72 Pixels/Inch so that the new graphic will work with common monitor resolutions.
To make the changes to your document, Click OK.
To change the canvas size, either adding additional space to the image or clipping space off of the image, select Image > Canvas Size. By default, Photoshop will add canvas in the background color that has been selected. You can add (or delete) width, height, or both. The grid in the center of the dialog box indicates where the original canvas is oriented. In the example at the right, extra space will be added to the top and sides of the existing image.
| Cropping an Image |
If you would like to only use part of an exisiting image, select the Crop Tool from the Toolbar ( looks like a square with a line through it).
You can
select the section you would like to keep by clicking a starting corner of
the section (typically you would start with the upper left) and hold down the
mouse button and drag the tool to the opposite corner (lower right).
This will create a dotted box around your selection, the part that will be cut away will be darkened and the inside of the selection will be normal brightness.
Move the Selection by clicking and dragging on the inside of it.
To Modify the Size or Shape of your selection, click and drag any of the boxes found in the corners and in the middle of the sides.
The image has not been modified yet. When satisfied with your selection hit Enter or Return on your keyboard. If you do not want to crop the image, hit Esc or click outside the cropped area or another tool.
| Adjusting Image Brightness and Contrast |
If an image is muddy looking or too bright, go to Image > Adjustments > Brightness/Contrast. If you have made a selection then only that selection will be changed (as seen below), otherwise it will change the entire image. Make sure Preview is checked so the changes are updated as you work. They will not be saved until OK is clicked. Setting Brightness and Contrast to 0 will return the image its initial state. When adjusting Brightness, it is best to compensate with Contrast. This will maintain the detail of your image. Lowering Contrast will "grey out" an image.
| Adjusting Image Hue and Saturation |
Open the image and go to Image > Adjustments > Hue/Saturation.
* Hue-
the color reflected from or transmitted through an object.
Changing the Hue will change the actual color reflected. Blue will become yellow with an increase in Hue. The effects of this can be balanced with Saturation.
* Saturation- the strength or purity of a color.
Increasing Saturation will make the colors more vivid and they will approach their Primary Color parent.
Decreasing Saturation will dull the image, and eventually , desaturating the image will make it Black and White.
* Lightness - works essentially the same way as Brightness.
Try different combinations of adjustments to get the most out of your image.
Return to Topics
| Adjusting Color Balance |
Click Image > Adjustments > Color Balance.
Color Balance is useful for color correcting poorly taken digital photographs or scans of poorly developed photographs. Often a photo will have a magenta or green tone like the left side of the image below. To counter a green discoloration move the Magenta/Green Slide toward Magenta (as seen on the right side of the image below). If the image is pink, slide toward Green. For overall picture adjustments, it is best to select Midtones in Tone Balance.

| Filters |
To apply an effect to an image, select a Filter from the pull down menus. To see a list and sample of all the filters, click on "Filter Gallery." Effects include artistic effects like brushstrokes, to textured effects like mosaic tiles or wind effects.

| Text Tool |
The Text Tool can be used to add text to an image. To input text, select the
Text Tool
, located in the Tools window.
If the Tools window is not open, go to Window > Tools. Tools should
be checked. Place the cursor where the text should begin, and type in the desired
text.
Text can be modified in a variety of ways, including for color, direction, style, size, justification, and color. These features can be edited by using either the Options window, or by using the Character and Paragraph palettes. These choices can be found by going to Window and then checking the desired pallete. If you may want to edit the text later on, save the file as a .psd so that the text layer can still be modified.
| Batch Processing |
Batch Processing is a procedure that can be split into two components: recording an action and applying the action. Before beginning, all the images that are to batch processed should be in one folder. Create a copy of this folder to use for the batch processing so that you may still retain the original images.
Recording an Action



Applying the Action

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