Lessons of Adobe Photoshop Basic (2)

In Photoshop 5.x, the crop tool is hidden under the marquee tools. In version 6 it has its own toolbar button. But the crop tool has a very easy keyboard shortcut to remember, so you'll rarely need to bother with selecting it from the toolbox. The shortcut for activating the crop tool is C. The crop tool in Photoshop can actually do much more than crop your images. As I mentioned in the last section, the crop tool can be used to increase your canvas size. It can also be used to rotate and resample images, and in Photoshop 6 it can be used to quickly correct the perspective of an image.

Let's start by exploring the most common use of the crop tool... cropping, of course! Open any image and select the Crop tool. To select an area to be cropped, just click and drag in your image and when you let go, the crop marquee will appear. There's no need to be precise when making the first selection, because you can edit your selection before committing to the crop. You can always save some time if you get it right the first time; however, the default crop cursor makes it somewhat difficult to see exactly where your selection begins and ends.

The selection point actually begins and ends at the very center of the crop tool, approximately where I've placed a red dot in the screen shot here. If you want exact precision however, you will want to switch to a crosshair cursor. At any time, you can switch from standard to precise cursors by enabling the Caps Lock key. This works with the painting tools as well. Try it out. You may find that the precise cursor is hard to see in some backgrounds, but it's nice to have the option when you need it.

OK, now pick which ever cursor preference you like and drag out a crop selection on your image. Notice the hollow boxes in the corners and on each side of the selection marquee? These are called handles because you can grab onto them to manipulate the selection.

Move your cursor over each of these handles and you'll notice it changes to a double pointing arrow to indicate that you can resize the selection border. Make some adjustments to your crop selection now using the handles. You'll notice if you drag a corner handle you can adjust the width and height at the same time. If you hold the shift key down while dragging a corner handle it constrains the height and width proportions.

You'll find if you try to move the selection border to just a few pixels from any of the document edges, the border automatically snaps to the document edge. This makes it nearly impossible to trim just a few pixels from an image, but you can disable this snapping behavior by holding down the Ctrl (Windows only) key when you get close to an edge. On Windows or Macintosh, you can toggle snapping on and off by pressing Ctrl/Command-; or from the View menu.

Notes for Version 6.0

In Photoshop 6, the cropped area is shielded with a gray screen. This makes it easier to visualize how the cropping affects the overall composition. You can change the shielded area color and opacity from the options bar after you make a crop selection. You can also disable the shading, by unchecking the "Shield cropped area" checkbox.

Now move your cursor inside the selection marquee. The cursor changes to a solid black arrow indicating that you can move the selection. Holding the shift key while you move the selection constrains your movements.

But that's not all... move your cursor to just outside one of the corner handles and you'll see it change to a double pointing curved arrow. When the curved arrow cursor is active you can rotate the selection marquee. This allows you to crop and straighten a crooked image at the same time. Just align one of the crop edges to a portion of the image that should be horizontal or vertical, and when you invoke the crop, it will rotate the image to conform to your selection. The center point on the crop marquee determines the center point to which the marquee is rotated. You can move this center point to change the center of rotation by clicking on it and dragging.

Notes for Version 6.0

In Photoshop 6, after you draw the crop selection, you have a checkbox on the options bar to adjust the perspective. This is useful for photos of buildings where there is some distortion. When you select the perspective check box, you can move your cursor over any of the corner handles and it will change to a shaded arrow. Then you can click and drag each corner of the crop marquee independently. To correct perspective distortion, move the top corners of the selection marquee inward, so that the sides of the selection are aligned with the edges of the building you want to correct.

Notes for Version 6.0

In version 6 you can also use the check mark button on the options bar to commit to the crop, or the X button to cancel the crop.

If you change your mind after you've made a crop selection, you can back out of it by pressing Esc. To commit to your selection and make the crop permanent, you can press Enter or Return, or simply double click inside the selection marquee.

Notes for Version 6.0

In Photoshop 6, if you are cropping a layered image, you can choose whether you want to delete the cropped area permanently, or just hide the area outside of the crop marquee. These options will appear on the options bar. The hide option retains those pixels, but resizes the canvas so they are not visible. This area outside the visible canvas is called "big data" and you can make it visible again by choosing Image > Reveal all. The delete/hide options will be dimmed when cropping a background layer or when using the perspective option. Keep in mind that the hide option requires more memory and disk space when you save the file.

Take a few moments now to practice cropping and manipulating the crop selection using all the methods we've discussed so far. You can return your image to its original state at any time by going to File > Revert.

I also mentioned that you could resample an image via the crop tool. To do this you'll need to use the crop options palette (or the options bar in Photoshop 6). The options palette for any tool can be accessed by double clicking on the toolbar button.

In the crop tool options, there is a check box for Fixed Target size. When this checkbox is activated, you can alter the image resolution. The Front Image button fills in the fields with the current image size and resolution, otherwise, the last used numbers will be remembered. Resampling with the crop tool is a bit difficult to describe; I suggest you read about it on page 59 of the Photoshop 5.0 User Guide (or look up Fixed Target Size Option in the online Help) and experiment with it to get a feel for how it works.

Lesson 2f Exercise: Crop Tool Practice

Now let's get some practice working with the crop tool. Right click each of these files names and download the images to your computer so you can practice these exercises:

The exercises on this page are for users of version 5.x or 6.0.

Practice Exercise 1
Changing Shape, Increasing Canvas Size & Adding Borders

Before Cropping

After Cropping

Crop the image to get the results shown above. Below is a screen shot of the approximate selection you'll need to make.

Next use the crop tool to expand your canvas size and add a black border to the image at the same time. First select black for the background color. Next make a crop selection and drag the borders outside of the document area as show to the left. When you're happy with the selection, commit to the crop and you should get something like the example here.

Practice Exercise 2
Rotating with the Crop Tool

Before Cropping

After Cropping

Crop the image to get the results shown above. Below is a screen shot of the approximate selection you'll need to make.

In Photoshop 5, you can also crop to a selection using the rectangular marquee tool. When a rectangular selection is active, just choose Image > Crop.

This concludes the crop exercises for version 5.x users. You may continue to the next section on the History Palette. Version 6.0 users can practice the additional crop tool features in the next page of exercises.

Lesson 2g: History Palette

Now that we've learned some basic commands for modifying images, it's important to understand how to undo these changes and correct mistakes. In learning about the Canvas Size command and crop tool, I snuck in a couple of ways for undoing your changes. These were Ctrl-Z/Command-Z for Undo and the File > Revert command.

You may have noticed already that the Undo command acts as a toggle for Undo and Redo, so you can only Undo the last action taken. And the Revert command takes you all the way back to the state of your image when it was last saved. So what if you want to undo more than one action, but you don't want to completely revert to the last saved state? That's where the History Palette comes in.

Let's look at the history palette now. At the top of the palette is a small thumbnail icon and the file name of your image. Whenever you open an image, Photoshop creates a initial "snapshot" of the image and lists it here in the history palette. A quick way to revert your image is to click this initial snapshot. You can add new snapshots to the history palette at any point by choosing new snapshot from the History palette menu or clicking the new snapshot button.

Try it now. Open any image, make some obvious editing changes such as changing the image size or cropping. Create a snapshot. Now click the first snapshot in the list. The image reverts to its original state. Click the second snapshot and you'll be returned to the edited version. Combined with the History Brush, snapshots can be a very powerful tool. We'll learn more about that later. For now, let's get back to looking at the History palette.

Below the snapshots there is a dividing line, and a list of all the recent changes you have made to the image. You can undo any of these recent changes just by clicking the last change you want to revert to, or by dragging the tiny arrow slider that appears next to each state. The slider is useful if you're not sure how far back you need to go because it allows you to preview the changes as you move it up or down.

By default, Photoshop only lists the last 20 actions you have performed on an image and anything older is purged from the list to allow more memory for Photoshop. If you have a lot of memory, you can increase this number through the History Options command in the History palette menu. If you'd prefer to keep more memory available for Photoshop, it's a good idea to get in the habit of creating snapshots of your image at key points throughout the editing process, then you can still revert to an earlier state.

Along the bottom of the History palette are three buttons. The first button creates a new document and works just like the duplicate command When you duplicate the image, all history states are deleted for the duplicate. The next button creates a new snapshot. This is quicker than using the menu command but it does not give you dialog box to name the snapshot. The snapshots will automatically be named in numeric sequence. The third button deletes the current state or snapshot depending on what is selected in the palette.

There's a lot more I could tell you about the History palette, but it is all explained very well in your User Guide (Pages 167-172 in the Photoshop 5.0 User Guide and pages 69-73 in the Photoshop 6.0 User Guide). We'll cover more about the History palette as required in future lessons, but if you want to learn more you can read these pages in your User Guide or the online help.

But before we move on, I just want to point out some important things you should know about the history palette and Snapshots:

• History and snapshots are not saved with an image. Closing and reopening an image will clear all history states and snapshots.


• Reverting to a previous state and then editing your image eliminates all history states that had come after it.


• Deleting a state deletes everything after it, unless the non-linear option is selected.


• Ctrl-Alt-Z/Command-Option-Z moves backward through the history states.


• Ctrl-Shift-Z/Command-Shift-Z moves forward through the history states.

Lesson 2h: Saving Images

Now that we've covered some of the more basic editing functions in Photoshop, you're going to need to know how to save your images.

To save an image in the native Photoshop file format, you would simply choose File > Save or Ctrl-S/Command-S. To save the file under a different name, you would choose the File > Save Ascommand (Shift-Ctrl-S/Shift-Command-S).

Where things can get tricky is when you need to save the file in a different format. If you have Photoshop 5.5 and you're saving an image intended for the Web, it's best to use the Save for Web command (Alt-Shift-Ctrl-S/Option-Shift-Command-S). Save for Web allows you preview up to four different settings and compare the results before committing to the Save. One important thing to know about Save for Web is that your image will always be exported with a resolution of 72 ppi, so if you need to retain the print size and resolution, it's best not to use Save for Web.

For more on the Save for Web command, see my overview for descriptions of each element:
When saving your class assignments for these lessons, get in the habit of using the Save for Web command since your assignments will be posted to the forum.

For more on saving images and file formats, visit these links:If you are using Photoshop 5.0 or you need to save to another format that's not for the Web, you'll want to use the Save A CopyCommand (Photoshop 5.x only).

Congratulations! It may not seem like we've covered very much, but you now have all the skills you need to prepare images for posting on the Web, sending via email, and printing on your home printer.

Lesson 2: Review

Before moving on to your assignment, take a few moment to refresh your memory on what we've learned in this lesson

Spacebar = Hand tool

View > New View to view the same image at different magnification.

Right click/control click on the title bar for easy access to common document editing functions including Duplicate, Image Size, andCanvas Size.

As you increase the print dimensions, your resolution decreases (thus, print quality decreases).

As you increase resolution, the print size must decrease based on the amount of pixel data available.

If you do not have enough pixel data to get the print size and resolution you need, then you'll have to the image.

Edit > Undo (Ctrl-Z/Command-Z)

Hold down the Alt/Option key in any dialog box and the Cancel button will change to a Reset button which you can then press to restore your original values.

Crop Tool = C

The Caps Lock key toggles between standard and precise cursors.

Shift key constrains movements when dragging selection border.

Prevent the crop border from snapping to the edge of your canvas by holding down the Ctrlkey (Windows only) or pressing Ctrl-;/Command-;.

Use the Fixed Target Size Option of the crop tool for changing image resolution while cropping.

File > Save (Ctrl-S/Command-S)

File > Save As (Shift-Ctrl-S/Shift-Command-S)

Save for Web (Alt-Shift-Ctrl-S/Option-Shift-Command-S)

Lesson 2: Homework Assignment

Your assignment for Lesson 2 incorporates most of the commands and tools you have learned so far

First find an image of yourself, a pet, a child or grandchild, etc. If you don't have any digital images of your own you can use, find one on the Web or in a CD image collection.

Open this image in Photoshop and crop away any unnecessary portions of the image. You want to give the image a clear focal point and eliminate the distractions. If the image needs straightening, do that also when you crop it.

Next resize your image so that neither the height or width is more than 200 pixels in dimension.

Pick a background color other than black or white and add a narrow border to the image either with the canvas size command or the crop tool.

Save the image as a JPEG using the Save for Web command. Experiment with the JPEG quality settings and observe the file size as you do. Try to find the best compromise between file size and image quality.

After you export the image as a JPEG, return to the Save for Web dialog and this time choose the GIF option. Experiment with the color depth and dithering settings and observe the file size as you do. Try to find the best compromise between file size and image quality.

Photoshop 5.0 users: Since you do not have the Save for Web feature, you'll have to save your work using the Save a Copy command instead. The GIF option is found under File > Export > GIF89a. Even though you don't have visual comparisons with the Save A Copy command, I would encourage you to save several variations of your files using different settings and compare the results. Try to find the image with best compromise between file size and image quality and upload this image for your assignment.

Post both images in the Lesson 2 Assignment thread of the forum.

Optionally, you may practice cropping, resizing and rotating other images and post them as well. Post as many images as you like! Use this assignment as an opportunity to get to know your other classmates.

Bonus Assignment: Use the Fixed Width options for the crop tool to resample a photo of yourself to 100 by 150 pixels at 72 ppi. Go to your forum profile.

Lesson 3a: Color Primer

This lesson deals primarily with color and color selection methods. Because this is a beginner's course, we are not going to go into all the intricacies of working with color and understanding color theory, but you do need to understand some basic principles. For more in-depth discussion on color theory as it relates to graphics software, you can visit this site's . Otherwise, scroll down to begin this lesson.

Before you dig in to this Photoshop lesson, I strongly suggest you familiarize yourself with some terminology and basic concepts through the following links:

An introduction to color in print and on the Web, from Desktop Publishing Guide Jacci Howard Bear.

Images come in many colors -- and color comes in many flavors. The RGB colors on your monitor are not the same as CMYK colors of your printer. To get the best results, you need to know which color mode to use when in Adobe Photoshop so your images look good. Here's a short course on Photoshop's color modes." This article from ElementK Journals provides overviews of Grayscale, RGB, CMYK, and Lab Color modes.

GlossaryPlease review the following glossary pages for definitions of the terms used in this lesson. 

Lesson 3b: The Color Picker

Let's start by looking at the Photoshop Color Picker. Bring up the color picker by clicking one of the color swatches on the toolbox.

In my screen shot, black was the currently selected color when I brought up the color picker. Notice that there is a small circle in the lower left corner of the color picker area, this circle surrounds the selected color. Click anywhere else in the color picker and the circle will follow. (Continued below...)

Notice the two squares just left of the cancel button. The color shown on top is the currently selected color, the color on the bottom is the color you are replacing. If you see a triangle with an exclamation mark, it means you have selected a color that is .Below the out of gamut alert, Photoshop displays the closest color that is within the CMYK color gamut. If you see a small cube displayed, it indicates that the color selection is not " Below the Web safe alert, Photoshop displays a tiny swatch of the closest Web-safe color match. Clicking on either of the closest match swatches will change the selected color to the closest match.

Now take a look at all those numeric entry fields on the right lower quadrant of the dialog box. These allow you to enter numeric color values in a variety of ways. The default for the color picker is to choose colors by Hue. You should have a dot next to the H in the color picker if you are still using the default preferences. As you move the color picker from left to right in the large color box you are adjusting the saturation of the hue. Try it and you'll notice the numbers next to the S change from 0 (far left) to 100 (far right). Moving the color picker up and down adjusts the brightness of the hue. As you move the color picker up and down notice that the Bvalues change from 0 to 100 as well. To change the Hue, you can click in the narrow rainbow-colored strip next to the large color picker area, or you can drag up and down in this space.

For this course we will be choosing colors with the default color picker arrangement, so I am not going to cover the other numeric entry fields, but I would like to encourage you to explore them on your own. At some stage in this course I may ask you to select a specific color by its RGB values. In these cases, you would enter numbers in the corresponding numeric fields for R, G, and B. For example, the RGB values for 50% gray are R128-G128-B128 and would be entered like this:

Notes for Version 5.5 and 6.0

In Photoshop 5.5 and higher, the color picker will also have a checkbox to display only Web colors. This restricts the color picker to only displaying colors in the Web-safe palette. In addition, you also have a field where you can enter the color codes used in HTML. This field is indicated with the # sign.

Lesson 3c: Color & Swatches Palettes

In addition to the color picker dialog box, Photoshop provides two palettes for selecting color: the Color Palette, and the Swatch Palette.

The color palette provides a color ramp along the bottom of the palette for quickly picking an approximate color. As you move your cursor over the color ramp, it changes to an eyedropper. Clicking in the color ramp changes the foreground color. Alt/Option clicking on the color ramp changes the background color. The current foreground and background colors are displayed in the color palette in addition to the toolbox.

If a color is out of gamut, the color palette will also display the gamut alert.

The sliders in the Color palette allow you to refine your color choice by adjusting each slider or by entering values into the numeric entry fields. Right-clicking/Control-clicking on the color ramp allows you to change the way the color ramp is displayed. The Color Palette menu also allows you to change the way the color ramp is displayed, and allows you to change the sliders displayed on the color palette for selecting colors using RGB, HSB, CMYK, or other color spaces.

Notes for Version 6.0

In Photoshop 6.0, the color ramp has two larger areas with black and white swatches. This makes it a bit easier to select pure white or pure black from the color ramp.

We've learned so many options for choosing colors already, it's hard to imagine ever needing another one, but Photoshop has it! Take a look at the swatches palette now.

The default swatches are a generic set of colors, but the true value of the Swatches palette is in its ability to load custom swatch collections. With a set of custom color swatches you can restrict yourself to specific colors without having to remember any numeric color values. For instance, you can create a custom swatch from the colors in a company logo, and use those colors when working on other projects for the company.

Here's a few color swatch actions you can try on your own:

• Left click selects a foreground color


• Alt-click/Option-click selects background color in Photoshop 6.0. In Photoshop 7.0, Ctrl-click/Command-click selects the background color.


• When you move your cursor over an empty spot in the swatch palette, it changes to a paint bucket and you can click to add a new color to the swatches palette. (In Photoshop 6, you'll be prompted to name the swatch.)


• In Photoshop 6.0, when you hold the Ctrl/Command key down and move your cursor over a swatch, the cursor changes to a scissors icon and you can click to delete a color. In Photoshop 7.0, use the Alt/Option key to delete a color.


• To change the color of a swatch, select the new color using the color picker, move the cursor over the color swatch that you want to replace, and hold down the shift key. The cursor changes to a paint bucket and you can click to replace the old color with a new color.


• In Photoshop 6, you can double click on a color to rename it.


• You can revert to the default swatch palette by choosing Reset Swatches from the Swatches palette menu.


• You can also load, replace, and save swatch collection from the Swatches palette menu.

In the exercise that follows you will learn how to create a custom swatch collection from the colors in an image. There's also some additional notes for users of version 6.

Lesson 3d: Custom Swatch Exercise

You can imagine how time consuming it would be if you had to create a custom swatch collection by choosing and adding colors one at a time. You'll be glad to know that you can create a custom palette from the colors in an existing image.

Let's try it now using the About logo. Save this image to your hard drive and open it in Photoshop.
The image opens in RGB color mode. In order to create a swatch collection from an image, we must first convert it to a indexed palette image. To do this, go to the Image menu and choose Mode > Indexed Color.

The indexed color dialog box appears. You can read more about the options in the dialog in the online help, but for this exercise, just make the following selections:

• Palette: Perceptual
• Colors: 128
• Forced: None
• Transparency: unchecked
• Dither: None

Click OK, and the image is converted to indexed color mode, and the color palette of the image is displayed in the swatches palette (version 5.x only).

To save the swatches for future use, go to Image > Mode > Color Table > Save. Give the file a name and then cancel out of the color table dialog. Color Tables are saved as ACT files. You can store the files anywhere and load them from the Swatch Palette menu. When loading a color swatch the default file name is set to ACO, so in order to load the ACT file you'll need to change the Files of type menu to look for ACT files. Once the Color table is loaded into the swatches palette you can save it again as an ACO file for ease of use; this step is not necessary, however, since the swatches palette can load both ACO and ACT files.

You'll find some additional color swatch files in the Goodies folder in your Photoshop application folder.

Notes for Version 6.0

In Photoshop 6, you'll find some additional options on the Swatches Palette menu. Most noticeably you'll find that you can load swatches directly from the menu. As long as the ACO swatch file is located in your AdobePhotoshop 6.0PresetsColor Swatches folder, the swatches will be listed on the menu, saving you a few steps when loading custom swatches. If you add a new swatch file while Photoshop is running, you'll need to close and reopen Photoshop before they will appear in the menu. Another difference in Photoshop 6 is that you have the option to view swatches as thumbnails or as a list. The list view shows a larger color swatch with the color name next to it. In thumbnail view, you can still see the color names by holding the cursor over the swatch for a few moments. Also in Photoshop 6, you'll find there are two icons along the bottom of the swatch palette for creating new swatches and deleting swatches. You can drag swatches from the palette to these buttons to add and remove colors from the swatch collection.

Lesson 3e: Eyedropper & Info Palette

With the eyedropper tool you can pick up colors from any open image. The keyboard shortcut for the eyedropper is I. Simply click with the eyedropper in your image to change the foreground color. Alt/Option click to change the background color.

When the color picker dialog is on-screen, your cursor will automatically change to the eyedropper anytime you move it outside of the color picker dialog to an open document. Whenever a painting tool is active, can temporarily switch to the eyedropper to change the foreground color by pressing Alt/Option.

Double click on the eyedropper toolbox button for the eyedropper options (In Photoshop 6 the options are on the option bar.) The options allow you to specify a single pixel sample, a 3x3 average, or a 5x5 average. In most cases, the 3 by 3 average works well. This averages the color of the nearest 3 pixels surrounding the area where you click. You can also change the sample area options by right-clicking/Control-clicking anywhere in the image when the eyedropper is active.

The eyedropper can be used in conjunction with the Info palette to read color values from your images. Display the info palette, then select the eyedropper and move it over your image. By default, the Info palette displays the RGB and CMYK values, as well as the X and Y coordinates of the cursor. When making a selection, the Info palette also displays the width and height of the selection.

Notice the tiny arrows next to the eyedropper and crosshair icons on the Info Palette. You remember what that means, don't you? Yes... there is a menu under there! Clicking on the tiny icon pops up a menu that allows you to change the values displayed in the info palette.

Another thing to notice about the Info palette is that it gives you yet another way to identify colors that are outside of the CMYK gamut. As you move the eyedropper over your image, look at the CMYK values displayed in the Info Palette. When the percent (%) sign changes to an exclamation mark (!) it indicates a color that is out of gamut.

If you hold the Shift key down while the eyedropper is active, you can place color samplers on your image. These samplers allow you to continuously display color readings for specific points on your image. You can place up to four samplers in an image. Place a couple of sampler points on your image now and notice what happens to the Info Palette. It expands to show the sampler readings. These are useful for doing advanced color correction work.

To remove a sampler, hold the shift key down and move the cursor directly over the sampler target; the cursor will change to a pointer and then you can click and drag it outside of the document window. You can hide the samplers without removing them from the Info Palette menu. You can also choose the color sampler tool directly from the toolbox (hidden under the eyedropper), but it is much easier to just remember I for eyedropper and shift for the sampler tool.

Lesson 3: Review and Homework

Bitmap mode means the image consists of only pure black and pure white. A bitmap mode image is called a one-bit image and is also known as line art

Grayscale mode means that the image contains 256 levels of gray plus black and white. Grayscale mode is also called 8-bit.

RGB stands for red, green, and blue. This image mode is a full color image. Because it uses one 8-bit channel for each color -- red, green, and blue -- it is called a 24-bit color image (8 red 8 green 8 blue = 24).

CMYK stands for Cyan, Magenta, Yellow, and Black. This color mode is used in four-color process printing, and is not usually used during the editing process.

Index mode allows you to limit the colors used in an image to specific palette. The indexed palette can have up to 256 unique colors.

The  alert is a small triangle with an exclamation mark that appears when a color is selected that will shift when the image is converted to CMYK mode.

The  alert is a small cube that appears when a color is selected that will shift or dither on systems that cannot display more than 256 colors.

Whenever the cursor appears as an eyedropper, you can click to change the foreground color.

The keyboard shortcut for the eyedropper is I.

Holding Alt/Option down when a painting tool is active temporarily changes to the eyedropper for selecting a new foreground color.

You can place up to four color samplers in your image by holding down the shift key when the eyedropper tool is selected.

Homework Assignment:Select an image that has a pleasing range of colors. If necessary, crop the image to isolate the areas of color that are most pleasing. Convert the image to index mode. Save the Color Table (ACT) and then convert the color table to a custom swatch file (ACO) as described in. Post your swatch file to the forum to share with your classmates. Here's an example I created from the following image: