Image Colors
Images can be saved in a variety of different color formats. The most common of these formats are CMYK and RGB. The letters stand for the method used to compile color. CMYK uses four colors; Cyan, Magenta, Yellow, and Black (k). RGB uses three colors; Red, Green, Blue. RGB is the standard format for web publications, and CMYK is the standard for print publications. The reason for this has to do with basic physics. Computer monitors, obviously, use light to show colors. Red, Green, and Blue are the three primary colors, which can be used to compile any other color…as long as we are dealing with light. However, with printed materials, it works differently. For example, with RGB, the absence of color (that is R: 0, B:0, G:0) is black. With CMYK, the absence of color (C:0, M: 0, Y:0, K:0) is white. That is, when this value is sent to the printer, the printer receives the information to not print any amount of cyan, magenta, yellow, or black. On plain paper this amounts to white. Different medium, different methods.

The goal for printing color images, is to get them in CMYK format. Color printers and large printing presses only use the CMYK method to create full color (4-color) prints. Therefore, before a document with full color pictures is sent to a printing press, it must be in CMYK format. However, here at Harvest, we would prefer to receive your pictures in RGB format first, and then let us do the necessary conversions. This is because it is easier to deal with images in RGB format while we are making the enhancements before they are sent to press. Please see the section below on curves and levels [provide link].

Office suites work strictly with RGB images. This is one of the main drawbacks of these programs when creating a document for the press. If a full color document is submitted in a program which uses RGB (Microsoft Word, Corel WordPerfect, etc.), it either has to be converted using very difficult and costly measures, or rebuilt entirely from scratch. This is why it is unwise to create a document with these programs if it involves color.

Of course, there are other types of images besides RGB and CMYK. Grayscale is a color format that uses black and white, with many shades in between, to draw the picture. Grayscale is a good format to save your pictures as if you do not want to spend the big bucks for a full color job. An interesting option with grayscale images is that, once you save them as grayscale, you can then apply any color to it. That is, for example, if you have a one-color newsletter that you are going to print in blue, you can apply the specific color of blue to your grayscale image. The end result is an image that is blue and white, with the many shades of that blue in between. Grayscale images are considerably smaller in file size than their equivalent color images.

Lineart (bitmap) is another very useful format. Lineart images are black and white, in the strictest definition. No grays in between. They are very restricted in their use, but they do serve a specific function. Lineart images are very useful when all you need is a black logo off of an old piece of letterhead. Simply scan the image as lineart, and you get a file that is a fraction of the file size if it were scanned as color or grayscale. When dealing with text, it is sometimes easier to scan a piece of paper as lineart, versus typing it over from scratch and having to worry about formatting issues. And the reader will never know the difference!

Image Resolution
Resolution is probably the most risky attribute for images because it directly controls the quality of the output. It is very important that the resolution of your images meet the minimum standards for the job. The minimum standards, of course, vary depending on the job. A general rule of thumb is that images need to be at least 300dpi (dots per inch) for quality printing (lineart, since it is a different type of image, needs to be 1200dpi). Please note that this is the final resolution. An image that is one inch tall at 300dpi when printed 6 inches tall will only be 50dpi!!

If you have any questions about resolution, and what you can do to help control the quality of your images, please contact us.

Vector Attributes
Colors work differently with vector graphics. Since vector graphics are nothing more than a group of individual objects, you have to specify a color for each object. So, if your logo is a sunburst with your company name below it, you will need to assign the appropriate colors to each part. It is important to keep in mind how many colors you want to print with. So if you are printing with two colors (yellow and black), you can not have an orange sun, yellow rays, and black text. This is something which can be fixed on our end, however when dealing with more complex logos, this can quickly become difficult and time consuming (which generally means a longer turn around time, and a higher price tag).

Another interesting note on vector graphics is that you can apply a blending or shading between the colors. So if you had a two-color logo (light-blue and black), you could have a gradual blend going from one color to the other.

Resolution is not an issue with vector graphics because it is a device independent format (i.e., it does not have dots or pixels). It is, again, just a group of objects defined by scalable equations.

Curves and levels
There are many other attributes to consider with photos, such as curves and levels. Most of these more complex attributes are dependent on the specific printer or printing press. This is why we prefer to receive your picture files unedited, so that we can make the necessary changes that best match our presses.