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Downloads of the ASMP member logos, are provided on the download page in four PC formats and three Macintosh formats. The PC formats are Tagged Image File Format (.tif), Graphics Interchange Format (.gif), Windows Meta File (.wmf) and Encapsulated PostScript (.eps). The Macintosh file formats are Tagged Image File Format (.tif), Graphics Interchange Format (.gif), and Encapsulated PostScript (.eps) format.

If you are unsure how to download the file you want, or if you have questions about the files you downloaded then please follow this link for information about file downloads. For more specific information that will help you understand which file format is right for you begin reading the following section.

Choosing the right file for you

The most important question you must answer when selecting a file is what type of output do you want -- on-screen display and/or print?

Following are some guidelines for selecting the right file types to match your software applications and output.

About graphic file formats

There are three general classes of graphic file formats: bitmap, vector, and hybrid (please note this does not include native application files from page layout programs such as QuarkXPress or Pagemaker). You decide which file class to use largely based upon what your final output will be.

A bitmap image is a file class that describes images--pixel for pixel--at a fixed resolution. Bitmap images have limited flexibility. Most photo graphics are in bitmap formats.

Vector files are generally used for logos and flat colored, non-continuous tone images such as linear illustrations. Vectors are line forms described in mathematical formulas and can be scaled to any size--large or small.

There are hybrid file classes which take advantage of both vectors and bitmap images in a single file. Hybrid file classes generally produce fair results, but are least desired when you can identify the final output you want.

Each file class has several file types. For example, .eps (Encapsulated PostScript) is a type of vector file; tiff (Tagged Image File Format) is a type of bitmap file; and wmf (Windows Meta File) is a type of hybrid file. Each file type has an intrinsically ideal usage: print, screen display, or hybrid. Please refer to the following output options when deciding which file class and type to use:

Print

An .eps file is best used for print, since it can contain a vector format which is device (i.e., printer) independent and delivers the best output at any size/resolution for any printer. It is also designed with the print color space in mind--spot or CMYK colors. The problem with this format is that it looks terrible on screen because it uses an 8-bit dithered preview (low-resolution and bad color image) for positioning; but when it is output to a postscript printer it looks excellent.

Screen Display

Bitmap images (jpeg (or jpg), tiff (or tiff), bmp, gif, psd) are best used for screen display, because they present the best possible image on screen. The problem in using a bitmap file is that it is limited to the resolution at which it is created. To get good print quality it has to be a hi-resolution file which means a large file. If you use a small, low-resolution file, the images then print out blocky while they may look good on-screen. When printing screen display file formats, you can also have a color shift if the file is in RGB instead of CMYK, because most color printing devices are designed for CMYK color space.

Formats for print and on-screen displays

Windows Meta File (wmf) for the PC and PICT files for the Mac are the best formats if you need to print a file and use it for an on-screen show. Newer versions of Microsoft Office for the Macintosh (98, and 2001) support wmf files, and can be used with good results. They provide similar print quality to the .eps format but also look reasonably good on screen. The limitation of this file format is the print quality is not as good as an .eps file and the screen version is not as good as the bitmapped version. Microsoft created the wmf file format and therefore supports it throughout their software applications. When working in Microsoft software, you are best off using a wmf if it can produce the quality you desire.

Quick hints

For print--use .eps
For display--use any bitmap formats (jpeg (or jpg), tiff (or tiff), bmp, gif, psd)
For both print and display--use PICT, wmf

Using logo files in PC or Macintosh applications

Each software application has its own menu for inserting files, pictures, etc. into a working file. For example, when using Microsoft Word or PowerPoint on the Macintosh or a PC, go to the "Insert" menu and select "Picture" then "From file." Then in the dialog box navigate to the downloaded file (for instance "asmp_red.gif". The file will be embedded into the open document, at the insertion point you designated. You may then resize or move the file as needed.

Understanding desktop color

To use color in a desktop publishing environment you will need to understand the different types of color spaces. Color space is the way color is described in an electronic file. Just as color is discussed as "additive" or "subtractive" in the physical world, there are ways to describe color in an electronic world. Here are a few:

CMYK

CMYK (cyan, magenta, yellow, and black) is considered a "four-channel" color space because it describes all color as the combination of some percentage of its four base colors: cyan, magenta, yellow, and black. CMYK color is used in files that are created for printing to a four color (hence the four channels) printing system. These include some desktop color printers and most high-end, offset printing presses. CMYK color files are typically used for images that will ultimately be printed as ink on paper.

RGB

RGB (red, green, blue) is a three-channel color space because it describes all color as the combination of some percentage of its three base colors: red, green, and blue. RGB color is used in files that are created for use on-screen or for projection (such as projection images, video, and animated multimedia). This includes most files used in Powerpoint for screenshows.

Index color

Index color is usually a derivative of RGB color. For example, the 256 colors used in a system palette for your computer are an index of thousands of possible colors. Colors used on the World Wide Web are usually an index of colors from many others. Index color palettes are used when you need smaller files that will render--or draw--to the screen fast. This is why most Web images are indexed.

Hexadecimal color values

The World Wide Web uses a unique color system defined as hexadecimal values. "Hex" values will always have an RGB equivalent value because they are indexed from an RGB palette. These "hex" values are designed to render smooth and accurate colors across many platforms and many browsers. While there are hex values that do not render well across all browsers and platforms, there is a fixed set that does. Widely referred to as the "Netscape palette," the "hex" palette used to explain color for the Web is the best way to define HTML type color and background colors for a web page.

Quick hints

Below is a list of some common desktop applications and the color spaces that are optimal for those applications:

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