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Following is some information that will help you (and your customers) make sure that jobs are set up to print at the highest possible quality. We also want to help you be able to explain why the "camera-ready" art you received has to be redone! Our goal is to make things as easy as possible on all fronts and help your customers understand what it takes to get a project printed. In order to keep it simple, we have tried to give you the basics, and welcome any other questions you may have. If you would like to order printed copies of this information with your company logo, contact us! Here is an abbreviated list of printing and typesetting terms. Here is a quick history of typesetting in general and a history of printing.

Several Reasons. Most web graphics are low resolution - usually 72 dpi (dots per inch). Color separation is often a problem... just because you see the colors you want doesn't mean the graphic will print separations as needed. Web graphics use an Indexed color or an RGB color space instead of the Spot Color or CMYK color space needed to print. File formats are sometimes not supported in high resolution printing and resizing the graphics can cause it to become blurry or pixelated. They are raster images (as opposed to vector images) that are resolution-dependant. In general, graphics created for the web don't have the quality needed to reproduce well in print.

The great debate... unless you are a mac user and then, for you, there is no debate! While we are mac lovers from way back - as most graphic designers are - I'll let you in on a secret... there's not a whole lot of difference since Bill (Gates) copied the mac operating system... I mean came out with Windows 95. While the operating systems are drastically different, the interface with the user is basically the same. So why one over the other? Anymore it comes down to personal preference. And "bang for your buck." Generally you can get more PC hardware for your dollars than Macintosh. Luckily for you we operate with and can handle jobs generated on either system!

Color is color - right? Wrong! There is a difference in the kind of color you see on your monitor right now and that color magazine on your desk. In order for a job to print you need to be able to separate the colors correctly. The transmissive color on your screen is called RGB - which means it has a Red, Green and Blue channel. This is referred to as an "additive" color space. The reflective color needed for print is CMYK - Cyan, Magenta, Yellow and Black (K) inks that mix together to create the full color you see in print. This is "subtractive" color space. RGB and CMYK make up the majority of the color you see in print or the web. For printing you will need color separations from your artwork. Simply put, color separations print out the different colors - whether CMYK or Spot colors - on different sheets so that the job can be printed. That doesn't mean that for a photograph you get one plate for every color you see... remember that full color pictures are composed of Cyan, Magenta, Yellow and Black inks that are printed on top of each other. It does mean that if you are working in the wrong color space that you will not get the separations needed to print. Other color spaces you want to be familiar with are: Indexed Color uses 256 colors or less which reduces the size of the file (used mostly for multimedia and web pages); Spot Colors - colors in print that are not made from the CMYK color space model. PMS (Pantone Matching System) is the industry standard for spot color inks. Here is an online PMS chart. It is VERY IMPORTANT when using spot color or duotone images to place into a document that you make sure that the name of the colors are exactly the same in both your image and your document or separations will not print correctly. Duotone, Tritone or Quadtones that create a two color, three, or four color image with overprinting spot colors; Bitmaps use one or two colors values, black or white to represent an image; and Grayscale uses 256 shades of gray.

Ahhh, resolution.. you need to make sure that you have enough for the job. And we're not talking about the ones you made in January! Resolution refers to the dpi (dots per inch) or ppi (pixels per inch) that you create or scan a graphic in at and the dpi that you will be outputting your job at. DPI is just what it sounds like - it means the number of dots (or pixels) per square inch that the graphic is input or output at. Anything that you print, whether on your laser printer or a high-end imagesetter, is made up of a this series of dots (pixels). Ever wonder why your type and images look so much better when you have film output than what you ran on your laser printer? It is because most laser printers are 300 dpi as opposed to the 2400 or more dpi on an imagesetter. Since the output is made up of more dots per square inch on the imagesetter, you have smoother lines because the dots are closer together. Pretty easy concept - so far anyway! This is called "output resolution." Now for your "input resolution"... there is a rule of thumb for graphics that you scan in or create in Photoshop or a similar program that are resolution-dependent (raster images - explanation for that term is under File Formats). For high-quality raster art graphics, you must have resolution at least equal to one and one-half times the line screen when using at 100% of size. Some people just do everything at 300 dpi... a throwback to the days when color seps were done at 150 Line Screen and the conventional wisdom was that you had to double the line screen - but no more. If you don't understand what line screen is check out the explanation further down the page. For example, if you are printing out a job at 150 Line Screen, then you need at least 225 dpi input resolution on your graphics to ensure high quality printing, or if you are printing at 100 line screen you would need at least 150 dpi input resolution. If you plan on resizing your graphics in another program, you will need to make sure that your "effective resolution" will support it. Effective resolution is the dpi that you get when resizing a graphic. As the size goes up in a raster image, the resolution goes down (or as the size goes down the resolution goes up). If you're original graphic is 4" wide at 300 dpi,and you placed it in your program and enlarge it to 6" wide, you have cut your effective resolution in half to 150 dpi or if you resize it to 2" wide, you have raised your effective resolution to 450 dpi. It is generally not a problem to have more resolution than needed, but it definitely is if you don't have enough! Ever see a printed picture that has the "jaggy" edges to it (pixelated) or is blurred and out of focus? Chances are these pictures did not have the resolution needed for printing. So much for easy!

Line screen (lpi) deals with a different type of dot than resolution. It refers to "halftone dot" - a pattern of very small black dots that simulate the different shades of gray. All printed photographic images or screened colors are made up of halftone dot. Grab a newspaper and a glossy magazine for this lesson! Look closely at the pictures in the newspaper... see how if you look, you can see dots that make up the picture. Now look at the magazine. See the dots there? Probably not with your naked eye. Look at it thru a magnifying glass.. now you can see the dots. Notice on the color pictures how the dots use all four colors (Cyan, Magenta, Yellow and Black) to form a rosette pattern in the picture. The lower the line screen - the newspaper is probably 85-100 line screen - the more prominent the dots. That is because line screen means the number of halftone dots per square inch that make up the image. The rosette pattern you see in the magazine, which is probably 150-200 line screen, is a result of the screen angles that the job was printed on. Since all images are made up of dots, you have to print the inks on top of each other - but just try to exactly line up a four different sets of dots and not get moiré (an unwanted "pattern" that appears in photos when the screen angles are not correct.) So each color is output at a different angle (generally a change of about 15 degrees for each color) to form the more visually pleasing rosette pattern that you saw. So why not print everything at 200 line screen to make it look better? Who wants to see the dots? Different types of papers and presses can only handle certain line screens. Look again at the newspaper - it is printed on a newsprint paper that absorbs ink and cannot handle a higher line screen with out plugging (plugging is when the ink fills in the space between the halftone dots). Look at the glossy magazine - it is probably printed on something like 80# gloss text (the weight and covering of the paper) and absorbs less ink; printing a cleaner dot that won't plug as easily allowing you to print at a higher line screen. If you ever have any doubt about what line screen to use on your job, check with the shop that will be printing it.

Once you have created that great looking graphic.. how do you get it from your screen to the printed piece? First let's define the two types of graphics that are generated from a computer. All photographs and graphics created in Image Editing programs (such as Photoshop or Corel Paint) generate a file that is a "raster" image. That means that the quality of the image is dependent on the resolution and size that it will be printed at - "resolution dependent." (See the section on resolution for a discussion of how all that works.) Resizing of the graphic will change the quality. Programs such as Illustrator, Corel or Freehand can create vector art files (as well as being able to export raster images). Vector art is not dependent on resolution and can be used at any size and resolution without loss of quality.
Now what about all those different formats in the "save as" dialogue box? The format that you select here helps determine how your picture will look when output. Vector Images are saved in EPS (Encapsulated Postscript) and WMF (Windows MetaFile) format for placement into other programs. Note that if you are working on a Windows system without a postscript printer, your printer cannot accurately use the EPS format for printing. Both formats are editable and can generally be imported or opened in a vector art program since they are self-contained pieces of coding. This is the preferred format for logos since they are easily editable and can be used at any size. Raster art can be saved in a variety of formats... including the EPS format listed above, but we are just going to talk about the most common formats here.
Let's start with the formats that are common to both the Macintosh and Windows systems. With the onset of digital photography and online pictures - JPEG (.jpg) is probably the most common. JPEGs are files that have used a compression method to keep the size of the file down. For print media, use a maximum or high setting. For web (depending on size and load time) use the medium to high setting. These are continuous tone images (such as photographs) and do not support any kind of transparency. JPEGS are usually not the preferred format for your print professional - generally they will prefer a TIFF format (Tagged-Image file Format - .tif). This is an easily cross-platformed image format and it is supported by virtually all programs. TIFFs can be used as RGB, CMYK or Grayscale color modes. Line art is usually saved as a TIFF also. Photoshop also has the ability to save it's layered files in a TIFF format, allowing you to keep one version of the file instead of a layered file for working and a flattened image to place. EPS files (as discussed above) can also be used on both platforms, but Mac files use a PICT or TIF preview and Windows files use a TIFF or BMP preview - so when saving Raster images as an .eps file remember to save the proper preview for the platform it will be used on.
Formats suitable for use on a specific system include the BMP (Bitmap format) for Windows and PICT for Macintosh. We prefer not to use these formats because of the limitations on cross-platforming and the quality.
To sum it all up - a TIFF image is your safest bet if you do not know what platform your pictures will end up on for Raster images. Each format has it's drawbacks, but we have found TIFF files to be the least troublesome. If you have any questions on what format to save a file in, contact us or your printer.
A Special Note on PDF files
When saving a complete job as a PDF you must remember a few basic rules. Always include all fonts in your job. Keep compression to a minimum - saving with a maximum quality setting. If at all possible, view your PDF file on a computer that does not have access to images and fonts you used in the file to make sure that all pages, fonts and images are appearing. Most printers now accept files in PDF format for output - but the responsibility for the set-up will be yours, so always check with your printer to ensure you are using the settings compatible with their system.

So your graphics are done, you have them all saved in the correct formats, color spaces and with enough resolution to print at the requested line screen. You even understand the statement about using web graphics that was made in the beginning of the page. Feelin' pretty good now - right? Well, don't want to burst your bubble, but if you just copied and pasted that graphic into Pagemaker, Quark, Word, Corel, Publisher or about any other program - then you just undid all that great work. That is the "how not to" of linking images. Rule Number 1 - Don't copy and paste your graphics from one program to another! This is different than placing a graphic into a layout and then copying it WITHIN THE SAME PROGRAM. On a Windows system (but not so much on a Mac OS) it is very easy to copy and paste from program to program, but the graphic is copied in an RGB format that all programs can understand, which makes it lose all that encoding you had in place to begin with. When using a graphic you have created in another program you need to use the "place" or the "import" command, usually located in the File menu. When you use this command the graphics - with all of the encoding that tells it how to print - becomes part of the file and the graphic can be printed in high resolution. Once you have properly placed or imported your graphic, and have your document ready to go to the printer, just make sure that you send a copy of the original graphic. Some programs will "embed" the image (the program stores a full copy of the graphic in the encoding for the document) or it will just "link" to the image - meaning that the program just puts a reference to the original graphic in the document encoding. Sometimes the printer may need to modify a picture because of printing conditions (dot gain, paper stock) and if the image is embedded, they will need the original graphic to make any changes.

Besides the graphics that you need to include with your document, you also will need to include any fonts you may have used. Not all fonts are created equal and some fonts will not print well in high resolution or may lock up a high resolution imagesetter. Fonts fall into two basic categories - Serif and Sans Serif. If you are viewing this as intended.. the font you see on the page is either Verdana, Arial or Helvetica - all of which are sans serif fonts. Notice that there are no extenders (or serifs) on any of the letters. Here is an example of a serif font - this font is Times or Times New Roman depending on your computer and browser. See the serifs on the ends of the main strokes. There is also Script fonts - like this one is. Fonts that are meant for headlines and titles are called Display fonts - they don't look very good as body copy and are often hard to read at small point sizes.
When sending your disk to the printer, you MUST include a copy of your fonts in order for your job to look like you want it to. If you are using Truetype fonts then you just need to send that font (on Windows they have a .ttf extension and are usually located in the c:\windows\fonts directory - on a Mac if you are not using a font management program they will be in the fonts folder inside the system folder). If you are using Type 1 fonts, on a Windows platform you will need to send both the .pfm and .pfb file for the font for it to image correctly. On a Macintosh system you will need to send both the screen font (usually in a "suitcase") and the printer font. Not providing fonts with the job can delay it or force the printer to substitute a similiar font, which may cause your document to reflow. Need to match an existing font... but you have no idea what the name is? Send us a copy and we will help you to identify it even if you only have a few letters or numbers to go by!