Chapter 6 — Brushes and Colors
Keyboard Shortcuts
Keyboard Shortcuts relating to Brushes and Colors in Adobe Photoshop
Windows
| KEYS | Function | Description |
|---|---|---|
| D | Default colors | Press the "D" key (just the "D" key by itself) to set the foreground color to Black and the background color to white |
| X | Switch colors | Press the "X" key (just the "X" key by itself) to make the foreground color the background color (and vice-versa) |
| [ | Decrease Brush Size | Press the "[" key to reduce the diameter of the brush you're using; this also works with the Eraser Tool and many other tools like the Clone Tool, Healing Brush, etc. |
| ] | Increase Brush Size | Press the "]" key to reduce the diameter of the brush you're using; this also works with the Eraser Tool and many other tools like the Clone Tool, Healing Brush, etc. |
Mac
| KEYS | Function | Description |
|---|---|---|
| D | Default colors | Press the "D" key (just the "D" key by itself) to set the foreground color to Black and the background color to white |
| X | Switch colors | Press the "X" key (just the "X" key by itself) to make the foreground color the background color (and vice-versa) |
| [ | Decrease Brush Size | Press the "[" key to reduce the diameter of the brush you're using; this also works with the Eraser Tool and many other tools like the Clone Tool, Healing Brush, etc. |
| ] | Increase Brush Size | Press the "]" key to reduce the diameter of the brush you're using; this also works with the Eraser Tool and many other tools like the Clone Tool, Healing Brush, etc. |
What Are "Web Safe" Colors?
After you've seen the Adobe Color Picker dialog box a few hundred times you may notice a small check box in the lower left-hand corner
marked "Only Web Colors" (see image right) and wonder what it's for. Putting a check mark in that box limits the Color Picker to
only "Web Safe" colors, a legacy of the early days of the World Wide Web. So what are "Web Safe" colors?
In the mid 1990's graphics designers noticed that most computers couldn't display some specific colors in images because those color values were reserved by the operating system. Mac and Windows systems each had a slightly different set of "reserved" colors, but between them there were only 30 colors that were off limits. You wouldn't think that would be a problem; in a JPEG image which permits 16.7 million colors you could just shift one channel (R, G or B) by a value of one and you'd be fine. No human could see such a small variation in color. Problem solved.
Except... at that time (1990's) there were still plenty of people using computer monitor/video card combinations that could display only 256 colors. Hardware and software would calculate how to convert the image from 16.7 million colors to 256, but when you hit on one of those 30 forbidden colors each specific hardware/software combination could react differently. And though a 1-out-of-16.7-million difference is undetectable to humans a 1-out-of-216-color difference (256-30=216) can be very visible. Expecially where two blocks of solid color meet and they're shifted in different directions. This was more of a problem with background colors, borders and other solid color graphics than with photographs, but it was a real issue.
So the only way you could be sure your graphics would display properly on all computers was to limit yourself to a specific set of 216 colors.
Checking the "Only Web Colors" does just that. Open the Color Picker, check the box and see.
What you'll see in the Color Picker is something like the image at right.
The color preview pane wil show blocks of various solid colors depending on the position of the vertical slider to its right. It will limit you to just the 216 colors that are (or were, in 1995) "Web Safe". For these colors the Red, Green and Blue values can only be: 0, 51, 102, 153, 204 or 255.
Any time you have chosen a color that is not Web Safe (which is virtually all the time, given that there are 16.7 million colors that aren't Web Safe!)
the Color Picker will display a little cube-shaped notification icon next to the Current Color swatch (see illustration at right). Put the mouse pointer over the mini-swatch
just below this icon, as shown, and you'll get a Tool Tip that tells you what it's for: Just click the swatch and Photoshop will pick the closest color that is "Web Safe".
All this is a lot of bother for an issue that hasn't really been an issue at all for well over a decade. No one really needs to pay attention to "Web Safe" colors any more. But there's always a chance you'll meet up with someone who thinks it's important. So now you know how to explain that it isn't. Just be careful if it's your boss or a client — some people don't take kindly to being told they're wrong, even if they are wrong (especially if they are wrong)!
Now the only question is why Adobe still includes this feature in Photoshop. Sorry, but I can't answer that one...
How to Create a New File in Photoshop
One of the most basic tasks you'll need to be able to accomplish in Photoshop is creating a new image file from scratch. It's simple enough to do (click here for "Rules of Thumb" to guide you), but if you get it wrong you can end up with an image that's useless for its intended purpose. With that in mind, let's step through the basic proceedure.
1 — Is this image for Print or Web Use?
Before you begin you need to know the planned use for the image you're going to be creating:
• High quality print
• Casual print
• Newspaper
• Poster
• Web
2 — How large is it going to be?
Here's an important decision point because not only do you have to decide on an image size, you must know the unit of measurement in which to specify your answer:
• If your image is for the web (or a multimedia application) you need to know the size in pixels
• If your image is for print you need to know the size in inches (or cm) and the resolution (pixels per inch or per cm)
We'll look at both possibilities.
Making a New Image for Print
1 - Decide on what resolution (quality) you need.
Before even getting to the File > New, menu, you need to know what print medium you are designing for and what physical size your final printed image is going to be. The choice of print medium will determine the Resolution setting you need to use (a bigger number means higher resolution and better quality — as well as larger file size):
• Newsprint — 150 to 200 pixels per inch (ppi)
• Casual photo prints — 200 to 240 ppi
• High quality photo prints — 300 to 360 ppi
Unless otherwise specified, assume print images to have a resolution of 300 pixels per inch
If you're designing a magazine cover for a publication that's 8 inches wide by 10.5 inches tall and the editor tells you they need images at 300 pixels per inch:
8 inches at 300 ppi — 8 x 300 = 2400 pixels
10.5 inches at 300 ppi — 10.5 x 300 = 3150 pixels
So your image will be 2400 pixels wide by 3150 pixels tall
2 - Enter the Height, Width and Resolution
If you really can't do the math to work out the pixel dimensions, you can click on the units boxes to the right of the Height and Width boxes
and change the values to "Inches". Then enter your intended print size height and width in inches and the resolution setting
appropriate for your output medium in the Resolution and Photoshop will calculate the pixel dimensions for you.
3 - Enter the Resolution required for your print type
As before, color Mode = RGB, 8 bit can be left as-is. Making the background color Transparent is usually not needed; you'll generally set it to either White or Background Color.
4 - Click OK and you're ready to go.
Making a New Image for the Web
1 - Click on the File menu and choose New. That will open the dialog box on the right.
If you have properly set your Photoshop preferences as described in the book and on this web site
the dialog should look pretty much as shown. If the units next to the Height and Width boxes show inches instead of pixels
then you didn't set up Photoshop as instructed. For now, change the units to pixels.
2 - Enter the height and width of your image in pixels.
3 - In the resolution box enter "72" for no other reason than it's the traditional way of working for web images. It won't affect anything but the way the Type tool adds text in Photoshop. Here's an important fact to remember:
The resolution setting has no effect on the size of images on web pages!
Color Mode = RGB, 8 bit can be left as-is. You can set the background color option to Transparent if you're making an image that will require transparency; otherwise set it to either White or Background Color.
4 - Click OK and you're ready to go.
Rules of Thumb:
- 72ppi resolution for web images
- 300ppi resolution for print
- Know the image size in pixels for web images
- Know the image size in inches (or centimeters, etc.) and the resolution in ppi for print
- When in doubt make the image extra large – you can always make a large image smaller if necessary
- Double-check that your height, width and resolution settings are where you want before clicking "OK"