Images

As with fonts, it is very important to include all images used in a publication or ad when it is sent to your service provider/printer. Even if photos or graphics are placed in your layout, the original image must be available for the computer to access when your document is being printed. Otherwise - especially in the case of a color image - the resulting document will contain only a low-resolution "thumbnail" of the image.

There are three basic areas that must be addressed in order for an image to be reproduced properly: image size, resolution, and color mode.

Image Size

It is always best to size an image to fit its picture box exactly. The easiest way to do this is to utilize your image editing program's "Crop" feature. In PhotoShop, for example, you can select "Fixed Target Size" in the Cropping Tool window and enter the dimensions of your picture box. You may then crop your image exactly, maintaining the proper height and width proportions. You should never squeeze a larger image or blow up a smaller one to fit the picture box. Besides the danger of distorting the proportions, squeezing a larger image will add a great deal of needless memory space to your document (increasing the printing time, and risking crashes), and blowing up a smaller image will reduce the resolution and result in a fuzzy image. Scale your image to the box.

Resolution

Resolution determines the clarity of your image when it is printed. It is measured in "Dots Per Inch" (dpi), i.e. the higher the number of dots per square inch, the finer the detail. The proper d.p.i. for a given image is determined by what kind of publication you are creating.

Newspapers published at TSP are printed at a resolution of 85 "lines Per Inch" (l.p.i. - also sometimes referred to as "line screen."). Like a lot of printing terms, l.p.i is just old-fashioned newspaper jargon for d.p.i. Magazines, brochures, yearbooks and other publications printed on slick paper are usually printed at 133 l.p.i. A good rule of thumb for determining the correct resolution for your images is twice the l.p.i of your intended publication. Therefore, a newspaper photo or graphic should be about 170- 200 d.p.i., and a magazine image should be 266-300 d.p.i. Going higher than this does nothing for the clarity of your printed image and just uses a lot more disk space and memory. Always check with your printer to determine at what l.p.i he will be printing.

Resolution is best selected when initially scanning an image. Your scanning software will have a line or box where this value may be set. when in doubt, always scan at a higher dpi and reduce it later if necessary. Going from a lower dpi to a higher one later will produce a fuzzy or grainy image. The resolution may be changed in your image editing program. In PhotoShop, this setting can be found by going to the "Image" menu at the top, selecting "Image Size," and changing the number in the box called "Resolution."

Color Mode

Color publications printed by the offset press method (the most common type, and the type we use at TSP) are always printed in CMYK. This means cyan, magenta, yellow and black inks are overlaid upon each other in various combinations to produce any color needed. This is also called "Additive Color." Therefore, any color images submitted for publication to TSP should be in CMYK mode. This sounds simple enough, until you realize that computer screens use the RGB method of producing color. This means that the screen starts with black, and various combinations of red, green and blue are removed to produce any color needed. This is also called (guess what!?) "Subtractive Color." When you scan a photo or download it from the internet, it will in all likelihood be in RGB mode. It must be converted to CMYK before it can be printed. You can do this easily in an image editing program such as PhotoShop. With your image open, go to the "Image" menu at the top, select "Mode" and choose "CMYK Color." We spend a lot of time at TSP converting RGB images to CMYK, and it always increases the cost to the customer. Learn to do it as part of your layout routine. It shows that you know what you are doing and it saves money!

With black and white images, always submit them in "Grayscale" mode. Customers frequently scan b&w images in RGB mode and fail to convert them to Grayscale. This merely ads to the memory requirements of the printer, and sometimes causes the printer to separate the document into four color plates. Again having your service provider convert the images increases your printing costs.