Digitizing Your PDD

Adobe Photoshop 7.0 Basics

Adobe Photoshop is a powerful tool for editing images. In this guide, you will learn some basic image manipulation skills, such as:

basic color correction brightness and contrast cropping an image zooming in and out using the rubber stamp tool to paint over part of an image changing image size using the lasso tool to make a selection copying and pasting creating a composite image using layers
applying filters

Lesson I - Color balance, Contrast, Brightness, and Cropping

Using Adobe Photoshop, open the file carroll.jpg. This photo of the statue of John Carroll has a red cast and is very dark.

John Carroll

carroll.jpg

First, let's look at the color balance. Select Image from the top menu bar. Next, choose Adjust > Color Balance. The color balance menu contains slider bars which add or subtract a particular color from the overall image. To adjust a color, click and drag the arrow underneath the slider bar. Alternatively, a positive or negative number may be entered in the color levels fields, which correspond from top to bottom with the color sliders.

Color balance tool

To adjust the color in the Carroll statue photo, slide the arrow under the Cyan - Red control to -50 on the Cyan side. The number in the color level field corresponding to Cyan - Red will change as you move the slider. If the preview box is checked on the color balance menu, the image will change as you slide the arrow. Next, click OK.

Although the color balance has been corrected, the photo is still too dark. We need to adjust the brightness and contrast levels. Select Image from the top menu bar. Next, choose Adjust -> Brightness/Contrast. The brightness/contrast menu contains two slider bars. Moving the brightness slider to the left darkens the image, and to the right lightens the image. Moving the contrast slider to the left reduces contrast, while moving it to the right increases contrast. Alternatively, a positive or negative number may be entered in the fields next to the sliders.

Brightness tool

To adjust the Carroll statue photo, click and drag the brightness slider towards the right to +20. Next, click and drag the contrast slider towards the right, to +20.

To finish, let's crop the image. Choose the Crop Tool by clicking on the marquee tool, and holding down the mouse button. Drag the pointer to the crop tool and release the mouse button.

Next, place the cursor (now in the shape of the crop tool) in the upper left near the head of John Carroll. Click, and hold the mouse button down. Drag the cursor to form a box around the statue, and release the mouse button. There is now a box around the statue. Select Image from the top menu bar, and choose Crop.

carrollafter.jpg

To save your image, select File from the top menu bar. We don't want to save over the old image, so choose Save As and type a new filename. Make sure the image type is JPEG, and click OK.

Lesson II - Zoom, Rubber Stamp Tool

Open the file soccer.jpg. In this lesson you will use the rubber stamp tool to remove the leg on the left side of the image.

soccer.jpg

soccerafter.jpg

	First, zoom in on the leg to make the image easier to work with. Select the Zoom Tool (magnifying glass) from the toolbox. Move the cursor over the leg, and click twice to zoom to 300%. Next, maximize the window by clicking on the maximize button above the right corner of the image.

	Next, we need to make a snapshot of the grass to be used in covering up the leg. Select the Rubber Stamp Tool from the toolbox. Position the cursor (now in the shape of a circle) over an area of grass near the shoe of the leg we're erasing. Holding the "ALT" key down, click once and release the mouse button. Next, move the cursor over part of the leg, click once to stamp the grass snapshot over the leg. Continue until the entire leg is covered.

(Important note: while using the rubber stamp tool, avoid dragging the mouse to move the cursor - this causes the rubber stamp to resample the snapshot as the cursor moves. For best results, use the rubber stamp one click at a time).

To see the results, double click on the zoom tool to zoom back out to 100%. Use Save As to save your image.

Lesson III - Image Size, Lasso Tool, Copying and Pasting, Layers

In this lesson we'll use two images to create our very own UFO photo. Open the file uscapitol.jpg.

Before we get started, look at the top border above the image. This bar shows the filename, as well as the zoom percentage. If the image is displaying under 100%, maximize the window, then double-click on the zoom tool to see how big the image is at 100%.

This image is a bit large, so we're going to reduce the size. Select Image from the top menu bar, and choose Image Size. The first two rows of the Image Size menu show the width and height of the image in pixels. We're going to change the image to 75% of the current size. To change the size by using a percentage, change the Width measurement from pixels to percent. Next, change the Width size from 100 to 75 by typing in the box next to the word Width. Click OK.

Image size pallette

ufo.jpg	Open the file ufo.jpg. The UFO in this image will be selected, copied, and then pasted into the US Capitol image. Because we will be drawing around the UFO image to copy it, working with a slightly larger image will be easier. Zoom in on the UFO to 300%.

	Next, select the Lasso Tool from the toolbox. Place the cursor in the UFO image so that it aligns with an edge of the UFO. Click and hold, then draw around the UFO until you've come full circle. Release the mouse button. You should now have an oval shape of blinking dots around the UFO.

Select Edit from the top menu bar, and choose Copy. Now select Window from the top menu bar. At the very bottom, choose uscapitol.jpg to return to the US Capitol image. Select Layer from the top menu bar, and choose New > Layer. Click OK on the New Layer menu. Next, select Edit from the top menu bar and choose Paste. This pastes a copy of the UFO selection into a Layer on top of the US Capitol image.

Take a look at the Layers palette on the right side of the screen. (You may have to make the palette longer by clicking and dragging the bottom). Notice how there are two layers - the background (US Capitol) and the UFO (Layer 1). Layer 1 is highlighted, which means any work you do will be performed on this layer.

Layer pallette

Select the move tool from the toolbox. Click and drag the UFO to the left of the Capitol. When you're happy with the placement of the UFO, the file can be saved. However, in order to save this file as a JPEG, the layers must be flattened to a single layer. Select Layer from the top menu bar, and choose Flatten Image. Next, use Save As to save the file in JPEG format.

Final Capitol building with space ship
uscapitolafter.jpg

Lesson IV - Using Filters

Open the file tower.jpg. Using this file, you can experiment with various filters that come with Adobe Photoshop. Select Filter from the top menu bar. Choose Artistic > Sponge. On the Sponge menu, arrange the various slider bars until you like the preview image. Click OK. To undo the filter, select Edit from the top menu bar and choose Undo Sponge. Experiment with different filters on your own to determine which ones you like best.

tower.jpg

towersponge.jpg

Recommended Books

Photoshop masters: the latest artwork & techniques from the world's top digital artists / edited by AGOSTO Imprint Gloucester, Mass. : Rockport Publishers, Inc., c1998. (Lauinger Library Stacks, TA1637 .P56 1998)

Photoshop in a nutshell : a desktop quick reference, 2nd edition/ Donnie O'Quinn: O'Reilly, c1999. (Lauinger Library, Picchi Center, T385 .O68 1999, Library Use Only)
hotoshop for the Web, 2nd edition/ Mikkel Aaland: O'Reilly, c1999. (Lauinger Library, Picchi Center, T385 .A34 1999, Library Use Only)

Photoshop Power Shortcuts/ Michael Ninness: Hayden Books, c2000
(Lauinger Library, Picchi Center, T385.N574 2000, Library Use Only)

Developed and maintained by the Gelardin Center Staff. Used with permission.