At Prism Color, we have print specifications that must be followed when setting up your
art files to be printed.
Below is a guide to prepare files for print, covering applications in the Adobe Creative Suite. The examples used are for InDesign, but can apply to Photoshop and Illustrator. This is a basic guide to help people just starting out in the print design business or are looking to learn more about proper file preparation and print production.
CMYK NOT RGB
When you first set up your art file, it is important to pick the correct color space for the end result. Artwork designed for the web is always RGB because desktop computer, laptop, tablet and mobile phone screens are designed using the RGB color space. When it comes to print media, the correct color space is the CMYK color mode. By designing in this mode, you will have a better idea of how your colors are going to print.
The print files are separated into the 4 process colors. During the separation, screen tints comprised of small dots are applied at different angles to each of the four colors. The screened separations are then transferred to four different printing plates, one for each color, and run on a printing press with one color overprinting the next.
The composite image fools the naked eye with the illusion of continuous tone.
The black is referred to as "K" denoting "key", a shorthand for the printing term "key plate". This plate impresses the artistic detail of an image, usually in black ink.
Colors created without screens and dots, such as those found in the PANTONE MATCHING SYSTEM®, are referred to in the industry as spot or solid colors. From a palette of 18 basic colors, each of the spot colors in the PANTONE MATCHING SYSTEM is mixed according to its own unique ink mixing formula developed by Pantone. You probably mixed yellow and blue paint to get green in your youth. Creating a PANTONE Spot Color is similar in concept, but with the added need for precision.
Each color in the System has a unique name or number followed by either a C or U. The letter suffix refers to the paper stock on which it is printed: C for Coated paper and U for Uncoated paper. Also created without screens, PANTONE metallic and pastel colors are considered part of the PANTONE MATCHING SYSTEM.
Due to the gamut of the 18 basic colors, some spot colors will be cleaner and brighter than if they were created in the four-color process. Spot colors are commonly used in corporate logos and identity programs, and in one, two or three-color jobs, where color accuracy and consistency is important across all printed marketing materials.
In some cases, a spot PANTONE MATCHING SYSTEM Color is chosen when creating a 4 process-printed piece. The customer who is paying for the printing may chose to save money by simulating or converting the spot color to a 4 color process equivalent. While some colors can be simulated well, there are many that are outside the possible color gamut for that process and will look quite different. There are spot color to 4 color process conversion swatch books available which will give you a side by side comparison showing the difference in the colors. Please make sure your customer is aware of this possible color variance.
When designing your piece, we suggest picking colors from the CMYK palette for the majority of the design and only adding 1 to 4 spot colors. Spot color inks should be used for corporate brand colors or when you want to add a bright saturated color throughout the design and not just in one small area. This will ensure that your spot color choices were picked to enhance the design and warrant the extra cost to print them. Each ink color has it's own separate plate and press unit. Most of today's offset printing presses have 6 or 8 color capacities, which with the 4 process colors, only allows 1 to 4 extra spot colors to be used. Please check with your client to make sure these extra colors are within their printing budget!
What is Offset Printing?
Offset lithography operates on a simple principle: ink and water don't mix. Image information (art and text) is put on thin metal plates which are dampened by water and ink by rollers on the press. The oil-based ink adheres to the image area, the water to the non-image area. The inked area is then transferred to a rubber cylinder or "blanket" and then onto the paper as it passes around the blanket. The process is called "offset" since the image doesn't go directly from the plates to the paper, but is offset or transferred to another surface as the intermediary.
Why Use Offset Printing?
Consistent high image quality
Offset printing produces sharp and clean images and type more easily than letterpress printing because the rubber blanket conforms to the texture of the printing surface.
Quick and easy production of printing plates
Electronic computer-to-plate systems further increase the speed and ease necessary for today's quick turnaround time.
Longer printing plate life
Because there is no direct contact between the plate and the printing surface, the plates last longer. Properly developed plates running in conjunction with optimized inks and fountain solution may exceed run lengths of a million impressions.
Offset printing is the cheapest method to produce high quality printing in commercial printing quantities.
Individual ink zone adjustment
The press operator can fine tune the amount of ink on the fountain roller with screw keys. Most commonly a metal blade controls the amount of ink transferred from the ink trough to the fountain roller. By adjusting the screws the gap between the blade and the fountain roller is altered, leading to the amount of ink applied to the roller to be increased or decreased in certain zones. Consequently the density of the color in the respective zone of the image is modified. This adjustment is controlled electronically by the press operator enabling a much more precise result.
Four over Four (or 4/4)
If your piece is 2 sided and uses 4 color process or full color imagery on each side, the print job will be called "four over four" or 4/4. If you are printing only one side and the back is blank, it would be called 4/0. These are common printer's terms and should be used when describing your job.
For postcards, you might print 4/1: four color on the front and 1 spot color on
For business cards, you might print 2/2: 2 spot colors on the front and back.
Here is a diagram of the left corner area of a typical document for print design. It is important to keep your design elements within these parameters.
Trim Line: This is the finished size of the piece.
Live Area: This is the area that is considered safe to keep any important information (especially text) within.
Bleed: The standard bleed for a printed piece is 0.125" (1/8th in.). This means that any color that bleeds off the edge, must extend .125" passed the trim line on all edges. That includes images, flat color graphics and any text.
Crop Marks: These indicate where to cut the paper.
If you are sending a high resolution pdf proof from InDesign or Illustrator go under "Marks and Bleeds" and click on "Crop Marks" along with assigning the .125" bleed before saving or exporting.
Black or Rich Black?
When printing with black color, there are two types of black you can use.
Black – 100 K: can be used for body copy and barcodes
Rich Black – 40 C, 40 M, 40 Y, 100 K: should be used when using large areas of black coverage
Note: Rich Black specifications may differ from printer to printer, so you should ask them what they recommend.
Black (K) value must be 100% to create a rich black!
Below, you will see the difference between rich black and black.
Rich black should be used when there are large areas of black coverage in your design. It will create a rich, saturated, deep black.
InDesign and Illustrator both have "Appearance of Black" preferences. It is wise to turn on "Display all blacks accurately" so you can tell the difference as you are working.
Preparing a File with
If you decide to use a UV varnish/UV coating on your printed piece, all you need to do is select the image or text you want the varnish on.
To keep your work organized, I’d suggest creating a layer and a spot color named "varnish/spot" and then make sure this spot color you create is not already used in the file.
First, create your spot color in your Swatch Panel by clicking on "New Swatch" and then change the color type from default "process color" to "spot color".
Select the graphics you want to apply the UV coating on.
Add a new layer (name it Varnish), copy the graphics (command C), paste them and apply the spot color to the graphics on that new layer. In Illustrator, click on the new layer and paste in place (command B). In InDesign, right click and select "Paste in Place". This will place the duplicated graphics in the exact position of the original graphics on that new layer. If you add other graphics at a later time that you want coated, makes sure you duplicate them and paste them on that same varnish layer.
Below is an example of the same Prism Color logo image above but with a UV varnish/UV coating spot color applied to the symbol and not the logo text. This will tell the printer that the symbol graphic will get coated. You can appoint any color for the varnish. Just make sure it is a contrasting color that is not already used in your design. In this case light blue was used.
Collecting Files For Output in InDesign
In CC, collecting files is known as Packaging (in previous versions it was known as Preflight).
To collect and package your files in InDesign, go to File > Package.
A summary screen will pop up. Here, you will see any spot colors used, RGB images, image sizes and fonts in the file.
For a more detailed overview of each component, click through the navigation menu on the left side of the Package window. It is good practice to check these. You should also click on "Show Problems Only" to alert you of any issues you will need to resolve before packaging, Make sure you do not have any RGB images
linking to you document!
After review and you are confident that there are no problems, click "Package". A screen will pop up with personal information and instruction fields you can fill out if desired. After clicking "Continue", another screen will appear in which you can name your package and choose the location where it will be saved. At the bottom, make sure "Copy Fonts", "Copy Linked Graphics" and Update Graphic Links In Package" are checked. Then click "Package" and you are finished.
Summary of Preparing Print Files
in Adobe Creative Suite Applications: