CMPS 80c Assignment 1

Due by Thursday 1/17, 2002 by 4:00pm
See the section "Submitting homework in your CATS account with SSH" in Using BE109 for instructions on submitting your homework.

Objectives:

Become familiar with Adobe Photoshop for 2D Drawing and Image Processing, learn to use the PCs in BE 109, and to store files on zip disks. A complete explanation of how to use Adobe Photoshop is not possible in these notes. Further instructions will be given in class, or you can see the instructional staff for the class. There is also some online help. Note: you must have zip disks for storing and turning in assignments. You can purchase these at the bookstore.

Assignment:

For this assignment, you must create an image from two or more starting images using Adobe Photoshop. To receive credit for this assignment you must fulfill all of these conditions:

One starting image must be from a photograph of yourself, which you can get from a digital camera or by scanning in a photo of yourself. There is an image scanner in BE 109.
The second starting image must be of an actual location, where you will place the image of yourself. This image must be different from the image of yourself.
The sky in the final image must be created from scratch using the drawing capabilities of Photoshop.
You must include in the final image your name, year, and major, in readable text.
The final image must make it appear that you are in the location image (e.g., sitting on the beach) and that the background that your drew shows through (e.g., as the sky, or in a picture frame).
You must save both the photoshop format image (including the layers) and a standard format image (e.g., gif, jpg, etc.)

Starting Adobe Photoshop

The PCs in BE 109 should be always running and are open for general use. You log into these machines using your CATS password. However, this does not access your CATS storage space. You must save your work when you leave on a zip disk or copy it to your CATS account, or it will probably not be there when you return. Also, you should delete your files (e.g., move to the Trash) before leaving the computer.

You can start Adobe Photoshop by clicking on the icon at the left or following Start>Other Applications>Web Development>Photoshop and clicking on it.

You can start Photoshop either with a blank screen which you can paint, or with a digital image. For this assignment, start with a blank screen by choosing File>New. This will offer you some options before creating the window, but the defaults are fine.

Photoshop uses layers to create images. Layers allow you to combine images in various ways. Initially there is one background layer. Leave this blank. Create two new layers by selecting Layer>New>Layer twice. Alt-click allows you to select the layer you want to work with. The eye makes a layer visible or invisible.

Background Layer

Make the background layer active by selecting it at the right. Use the painting tools at the left to create a background image that will show through the two images that you will later read in. Tools include such features as a paintbrush, pencil, airbrush, and paint bucket. At the right, you can also modify the color and characteristics of the tool you are using. For example, for the assignment, you could create a background of clouds.

Notice that descriptions and instructions appear at the bottom of the Photoshop window. Also, you can always Select>All to make the contents of the window active, and Edit it in various ways, such as Cutting it.

Scanning or Finding Digital Images

You can scan in the images using the scanner in 109. Only one computer in the lab is attached to the scanner (there's a sign on top of it that says "Scanner Station").

To scan an image:

Put the image into the scanner, just as you would a copy machine.
Start Photoshop.
Choose the File>Import>Deskscan II 2.9 item. The scanner will perform preview scan (this may take a few seconds as the scanner warms up).
Photoshop will bring up a window that shows you the preview on the right, and scanning options on the left. You can drag out a rectangle of the area you want to scan in the preview picture on the right (don't worry if your image is upside down or crooked, you can fix that later with commands from the Image>Rotate Canvas menu). Just make sure you have everything you want scanned inside the rectangle.
In the scanning options side of the window, choose Sharp Millions of Colors from the Type menu.
You may also want to increase the Scaling of the scanned image. The higher the Scaling, the more detailed your scanned image will be. A Scaling value between 200% and 300% should be fine for most of your work in this class. Use the slider to adjust the scaling in large amounts, and the arrow buttons to make small changes. A higher scaling will also create a larger image, so watch the size of the image that will be scanned; if the size starts to read more than 20,000K (as in 20 MegaBytes), you may want to reduce the scaling size.
When you the scaling set, and the area you want to scan boxed, click the Final button to scan your image. Photoshop will create a new unsaved image, with the results of the scan in the Background layer.
When you are done scanning images, you can click the close button of the DeskScan II window. The close button is a small box with an X on it, at the right hand side of the window's blue title bar.
Don't forget to take your original image out of the scanner!
(Optional Step) Run these commands on your scanned image: Image>Adjust>Auto Contrast and Image>Adjust>Auto Levels. These commands tend to make the image clearer and closer to the original photo.

You may want to get a digital image from the web for your location. If you do this, be sure and credit the origin of the image when you demonstrate or describe your assignment. To get an image from the web, right click with the mouse on the image you want and save the image in the directory C:\UserTemp. You can also use digital images from other sources.

Opening and Processing the Images

Make the lower layer active. Use File>Open to read in the location image that you want to use. Move it away from the canvas you have created. Select the image that you read in, Edit>copy it, and click in the canvas window. Use Edit>Paste to place a copy of the image in the canvas. Then close the image.

Next make the top layer active and repeat the process with the image of yourself.

There are various things that you can do to make the images different. Play with the Filter choices. None are required for this assignment.

To allow the background to show through, you must remove a part of this layer. A good way to do this is with the Magic Wand. Select that tool and click on a region of consistent color that you want to delete, and then Edit>Cut it. If the layer and background are both visible, you should see the background through this region.

Now select and view just the top image of yourself. Select a region that includes you but nothing else. Use the Lasso tool to outline the part of yourself (must include your face) to retain. Use Select>Invert to change the selection to everything outside of your image. Use Edit>Cut to remove the outside. Now if you make all the layers visible, you will see yourself in the location image and the background that you drew behind.

Including Text

Select the Text tool and include your name and the other requirements somewhere on the image.

Saving the Image as a File

To save your work, use File>Save As... and make sure you move to the C:\UserTemp folder. At the top of the Save window, there is a menu labeled Save In. Click on this menu, and choose the drive labeled C: (you may have to scroll up to find it). Then double click on the UserTemp folder. The Save In field should read UserTemp. Type a name for your file in the field labeled File Name. Notice that underneath the File Name field is a field labeled Save As. This is a popup menu that allows you to choose the file format to save your image in. Only the Photoshop file format (.PSD), listed at the top of that menu, will save the layers, channels, and other information that make up your image while you are constructing it. Because of this, if there is more than one layer in your image, only the Photoshop file format will be listed in the menu. Until you are finished editing your image, you should always use the Photoshop file format.

Once you have saved your image once, as long as you do not need to change the format of the file (as you will when you finish), you can simply use the File->Save to update the file with your latest changes (you should save your work often, if the computer stops working or the power goes out, you will lose everything you have done since the last time you saved).

When you are finished, and you want to save your completed image, choose File>Save a Copy... to save your image with a different format. You may need to move to the UserTemp folder again (follow the instructions above if you do). Although the layer information is not saved, the image that is saved should look the same as the image with the layers. When Photoshop removes the layer information, it is called Flattening the image (i.e.. to a single layer). For now, you will find the JPEG file format best. It produces much smaller file sizes through a process called compression. If you choose to use the JPEG file format, Photoshop will present a window with options for the JPEG format. The only one you should need to look at is the Quality. Make sure the quality is as high as possible by typing "12" into the Quality text field. The small triangle underneath the Quality text field should move all the way to the right when you do this. Later on in the course, you will probably use Amiga IFF, Targa, or TIFF to save your images (while these formats are also compressed, the file size of the images they produce is generally larger than JPEG).

Remember you must submit your image in both JPEG and Photoshop (.psd) file formats. So do not create the JPEG version until you are all done; it does not contain the layers and other data we want to see.

Questions? E-mail Mark Slater and/or Jane Wilhelms.