Lesson 9: Can I Have That on Paper?
Advanced Adobe Photoshop Tutorials
Table of Contents
An Overview of Printing
The previous lesson introduced you to the world of publishing on the Web with ImageReady. We covered how to make animated images, how to keep your image size down, and much more. Now you're ready to print out some of those masterpieces. This lesson will show you how to print all those images you've created. It will dispel fears about color separations and halftone screens while showing you how to get your image to look great on anything from a $100 inkjet printer to a multimillion-dollar web press.
A couple of topics we'll focus on are the Print and Page Setup dialog boxes. I think it's important that you learn to successfully print all you've created thus far in this course.
I bet you never thought printing could be such a complex task did you? But many people make their livings ensuring the print quality of newspapers, magazines, and other publications. It's an involved process, and I don't expect you to be an expert when this lesson is said and done. My goal is to alleviate some of the uneasiness surrounding the printing process. So here goes!
Let's start with color separations. I've mentioned CMYK throughout the course, but this is where it comes into play. CMYK stands for cyan, magenta, yellow, and black. These are the four ink colors used in the professional printing process: it's often referred to as four-color process or process color.
Figure 9-1 shows how to create CMYK separations so that you can print to negatives; printing plates may then be made from those negatives. It is important to understand this process because you may need to use it for a piece of art you have created.
Figure 9-1: The top half of the Save As dialog box.
There are two types of Desktop Color Separations (DCS): DCS 1.0 and DCS 2.0. The difference between them is the ability to accept extra channels. When you save as either DCS file type, Photoshop creates a composite file and four other files -- one for each color (.C, .M, .Y and .K).
- DCS 1.0: All layers must be flattened and there cannot be any extra channels. You may have paths.
- DCS 2.0: All layers must be flattened, but you are allowed spot channels and a single alpha channel, as well as paths.
Note: If you don't have a PostScript printer driver installed on your computer, you will not see the four extra files that are created when you save as DCS.
Televisions and computer screens use the RGB spectrum (red, green, and blue) to generate images, while the printing process uses the CMYK inks as discussed above. Just like television and computer screens, printed pages are composed of a series of dots.
These dots are called a halftone screen. They control the amount of ink applied to specific parts of the page. In order for the page to take on the look of consistent color, each plate (ink) -- cyan, magenta, yellow, and black -- has a halftone screen applied to it. There is a very good example and description available from the Photoshop Help Menu. Choose Help > Help Topics, click on Search, and type halftone screen. Read the section titled Selecting Halftone Screen Attributes.
Note to Photoshop 5.5 users: Your help menu is different than the one in Photoshop 6.0. Choose Help > Help Topics. When the help dialog appears, click on Index and enter the words "halftone screens: explained . " This is the same example that appears in the 6.0 Help menu.
Dissecting the Dialog Box
The Photoshop Print Options (File > Print Options) dialog box can be somewhat confusing. Let's break it down:
The Page Options dialog box appears in Figure 9-2.
Figure 9-2: The Print Options dialog box.
- Preview: The white area in this box is the area of the page you chose in the Page Setup dialog box where the image will appear. The shaded area surrounding the white area is the edge of the page that won't be printed on.
- Position: This is where your image will appear on the page. In this case, my image will be centered on the page, beginning 3.042 inches from the top and 1.139 inches from left.
- Scaled Print Size: You can enter a percentage as the Scale value and this will enlarge or reduce the print dimensions of your image. The resolution will automatically be adjusted to compensate for the change in print size. This will only affect the current print; the values in the Image Size dialog will not change.
Numbers 4-11 are basically just an overview of what each function does. Most of you will probably never need or use these functions, but I want you to know what they are in case you do:
4. Background: Choose a color to be printed outside the image area. Let's say your image is 4 x 4 inches and you're printing on an 8 1/2 x 11 sheet of paper. There's going to be roughly 4 1/2 x 7 inches left over that will usually stay white (or the color of the paper). I say roughly 4 1/2 x 7 inches because most printers have to leave a certain amount of space around each edge so that it can move the paper through the mechanisms.
5. Border: Add a black box around the image.
6. Bleed: Place crop marks inside rather than outside the image so that, when trimmed, the image will extend to the edge of the paper. A picture that extends to the edge of a magazine or book page is created with a bleed and the page has had to be trimmed.
7. Screen: This box determines the lines per inch (LPI) for each plate: cyan, magenta, yellow, and black (if image is four-color process). If the image is grayscale, then the Screen will determine the LPI for the black plate only. LPI will be discussed in greater detail in the next section.
8. Transfer: You can set up a transfer function to compensate for a dot gain or loss and other press problems. If you are working with a commercial print shop, you should ask a pre-press professional there what transfer function to use and when, if it is necessary at all. If you are not working on an image for commercial use, don't worry about this function.
9. Interpolation: This option reduces the rough appearance that low-resolution images can develop during printing, but it can reduce the sharpness of the image as well. If you're not using a PostScript Level 2 printer, this function will not work.
Here is a group of options used to provide instructions to commercial printers.
Calibration bars: These are bars that print on the outside of the image to ensure the color is printing correctly. Again, unless you're working on a commercial job, this probably won't apply. If you're doing commercial work, I would leave it up to the professionals at the print shop, unless they tell you otherwise. It's always best to find out from the printer exactly what they need from you as the designer. Believe me, it makes the whole process much easier.
Registration Marks: Registration Marks are placed on the outside of the image to ensure correct placement of each plate so that the color isn't off.
Crop Marks (corner and center): Crop Marks show where the page is to be trimmed. They can be printed inside or outside of an image.
Caption: You can print descriptions below your images using this function. To add the text, choose File> File Info> Caption. Then check the Caption box in the Print Options dialog box.
Labels : This option prints the file name and the channel that was active when you began printing.
Emulsion Down: Honestly, I've never used this option so I don't think I could explain it properly. Here's what the Photoshop Help has to say, for your reading enjoyment.
"Makes type readable when the emulsion is down: that is, when the photosensitive layer on a piece of film or photographic paper is facing away from you. Normally, images printed on paper are printed with emulsion up, with type readable when the photosensitive layer faces you. Images printed on film are often printed down.
"To determine the emulsion side, examine the film under a bright light after it has been developed. The dull side is the emulsion; the shiny side is the base. Check whether your print shop requires film with positive emulsion up, negative emulsion up, positive emulsion down, or negative emulsion down."
Negative: This option is only used if you are printing directly to a negative so that a plate can be made. Check with your commercial print shop to find out if this is necessary.
10. Include Vector Data: Check this box if you are using vector or non-rasterized, type, or vector shapes such as Layer Clipping Paths. With this option checked, vectors will be printed without being rasterized.
11. Encoding: This defines the type of computer data the printer driver will transfer when printing. Photoshop uses binary data by default, which I suggest using unless you're told otherwise by your print shop. I just wanted to mention that you can choose JPEG or ASCII. JPEG will produce smaller file sizes, but information will be lost as a result, and JPEG encoding is only readable on PostScript Level 2 printers. Some scenarios will require you to use ASCII encoding, but this uses twice as much information as binary does.
Well, I know this section wasn't as exciting as some of the other lessons in this course have been, but it's information that is good to know. Next, we'll discuss the difference between dots per inch (dpi) and lines per inch (lpi).
Attack of the Killer Acronyms
This section is mainly an overview of a lot of the acronyms I've introduced in this lesson. (I'm assuming you won't mind a summary.) Anyway, let's get to the happy task of discussing CMYK, DCS, EPS, and LPI.
- CMYK: Cyan, magenta, yellow, and black are the four inks used in the printing process. They are also referred to as four-color process and process colors (Figure 9-3).
Figure 9-3: The four process colors.
- DCS: Desktop Color Separations. Choosing EPS DCS 1.0 or 2.0 from the Save As drop-down menu in the Save As dialog box (File>Save As) prepares your image for printing by separating it into four halftone screens.
- EPS: Encapsulated PostScript. You must have a PostScript printer in order to use this file format. The EPS format is used to transfer PostScript images between programs. It is supported by vector, raster, and page layout programs.
- LPI: Lines Per Inch is considered a screen frequency and is associated with Halftone Screening. You will not be able to see the Halftone Screen on your monitor; it is only visible on the printed page.
The dots composing the printed image consist of a series of lines per inch (LPI). The higher the LPI, the more detail can be produced on the page. Newspapers use a frequency of 85 LPI, while magazines use 133 LPI because of the difference in paper quality.
Let's take a look at some of the items in the Halftone Screen dialog box (Figure 9-5):
Figure 9-4: The Halftone Screen dialog box.
- Use Printer's Default Screens: This option is turned on by default and is probably the best choice, unless your print shop tells you otherwise.
- Ink: You can create a screen for each ink.
- Frequency: Choose the number of lines per inch (lpi) here.
- Angle: Choose the angle for the dot here. The most common angle is 45 degrees.
- Shape: Choose the shape of the dot here. The most commonly used shape is diamond, but there are several other choices.
- Use Accurate Screens: If you are printing to a printer with a very high resolution, use this option. Check with your print shop to see if it is necessary.
- Use Same Shape for All Inks: This option is on by default. It will ensure that each screen is composed of the same dot shape.
- Auto: Fill in the blanks and it will calculate the best screen frequency and angle.
Goodbye and Good Luck
Whew! We're done; do you feel smarter? I hope so. In this lesson, we covered a wide range of information on printing. We also went item by item through some of the more important printing dialog boxes. If you're printing vector objects, don't forget to check the Include Vector Data option in the Print Options dialog box.
In nine lessons, we covered a lot of material, from newfangled tools in Photoshop version 6 to acronyms. We've covered everything from Layer Masks and Layer Clipping Paths to creating rollovers and animations in ImageReady. I know you've had a lot of information presented to you, but you've done great. Go finish your last quiz and assignment and continue to read through your course text to hone your skills. Of course, if you have any questions or any suggestions, please post them to the Message Board. See you there!
Try Real World Photoshop 6: Industrial Strength Production Techniques by David Blatner and Bruce Fraser.
If you're looking for something a little less advanced, try Photoshop 6 for Windows and Macintosh: Visual QuickStart Guide, by Elaine Weinmann and Peter Lourekas.
Also, check out these sites:
www.photoshopuser.com -- Become a member!
www.planetphotoshop.com -- Contains resources and tutorials
www.designsbymark.com -- Tutorials and tips gurus.onlinedesignschool.com -- Tutorials and tips