Designing Print Ready Digital Artwork

First things first : 300+ dpi

DPI - Dots per inch
Print Ready Digital Artwork is different from the types of graphics or images used on the web. Images and artwork used for print need to be Higher Resolution (300 dpi) minimum. Internet resolution is normally 72 or 96 dpi, so that logo on your website will usually pixalate (become grainy) when it is stretched out to fit on a business card, letterhead or other printed medium. Depending on the final print-ready format requested from the commercial printer or print supplier, you may even use resolutions of 2400 dpi. In short, don't count on the website images to work for print.

File formats we use :

PDF - pdf - Use this format for postcards, brochures, even business cards, but you must get the dimensions and the printers marks correct. A 2.1" x 3.6" design in the middle of an 8.5" x 11" pdf without crop marks or registration marks, usually puts the printer through more hoops just to cut out and place your design for print. Using pdf does allow for higher dpi's, we recommend 2400 when making your pdf.

Tagged Image (File) Format - tif, tiff - This is great for business cards and smaller print dimensions. Use 350+ dpi to achieve the best clarity. Zip the tif, and then upload it, or use email. -- Most email accounts (Meaning yours) will have a size limit of 10 or 20 MB for attachments, but email has to be placed into a special envelope so you loose 20-30% on the size of your attachment, so a 20MB limit is really about 14MB. Some programs allow you to compress the tif/tiff file during the file saving step, you may not want to do this! If the printer can't uncompress the tif file, the artwork is no good and you may have to re-upload and incurr change order fee's, so zip the tif uncompressed!

JPEG - jpg, jpeg - Jpegs are great for the web, but not so much for the printing industry. You can use a jpeg for artwork if the printer allows this, but the color may shift and the resolution and clarity may not print as expected.

EPS - eps - EPS (Encapsulated Post Script) are files that use postscript printer instructions to define the curves, straight lines and other data within a graphic. There are several formats of eps that exists. Usually, eps graphics that do not contain an image layer are the most portable and compact. The advantage of this format is the ability to set small dpi requirements in the design program and then switch to high resolution for printing without changing the dimensions of the artwork.

In lay-man's terms:
Each format has advantages and dis-advantages of color, transparency, resolution and sharpness, compression and transportability. The higher the resolution, usually means a sharper image. The more colors used, the larger the file size. When compression is used, you risk loosing the sharpness of the image, but gain in transportability (as in an email attachment), but you may add an incompatibility with the printing software that runs the press if the file can not be de-compressed.

It has been my experience that tif and pdf are the best to use based on color preservation and the ability to use higher resolutions and keep the sharpness of images at their best. Business cards on paper work well at 350 dpi in tif format, but in a pdf you should go up to 1200+. What ever image viewing software you are using, you should be able to see the sharpness and cleanliness at 100% or at a 1:1 ratio. After 100% percent, back off to 50%. If you loose lines of text, or find that the image is pixalated at this viewing level, it may be a sign that your resolution is too low, or the font size is too small or thin. PDF's need to have the fonts included/embedded!

RGB or CMYK?

RGB stands for - red, green and blue. The different intensities of these three colors on a single pixal (dot) controls the final color and brightness you see on your monitor. Full intensity of all three will give you the color white.
CMYK stands for - cyan(blue/green), magenta(red/maroon), yellow and black (Key). The different percentages of these colors on a single dot control the amount of light filtering accomplished at a single point, the reflection is the resulting color you see on printed material. The surface of the paper, color of the paper, color temperature of the light being reflected, all have an effect on the final color and look of the printed material. Absence of all color will give you white or (Paper).

Take your business card or other colorful material and stand under a fluorescent light fixture. Then take that same card/material and look at it in natural sunlight. You will be amazed at how the colors change from one light source to the other.

Tune your monitor! Some newer computer monitors (Including LCD/Plasma) have the ability to set the gamma and temp of the monitor right through the video software. If it does, follow the wizard and tune for 6500, Or, you can download and use software that allows you to tune your monitor to emulate the commercial printing CMYK environment. Use gamma corrections and CMS profiles where ever possible. Set up for D65 not 9300K. Google the net for gamma correction and you'll find the rest.

What is color shifting/matching?

When we look at an image on the computer monitor, we see the emission of light from a reactive layer of phosphorus effected by the frequency and intensity of the electron beam used to excite the phosphorus. How that all works in detail is not important, what is important is that you are seeing the emission of light.
When we look at a piece of printed material, we are seeing the reflection of light that is filtered by the inks and coatings used on the material itself.
So, in general, we have the emission of light (your monitor RGB) verses the reflection of light (your printed material CMYK).

Here's is where color shifting comes into the process. The color spectrum available to the monitor is far greater than the filtering ability of the ink. To solve this difference in spectrums, the industry came up with some mathematical formulas to convert from RGB to CMYK or vise-versa. However, the formulas are not completely accurate, and do not allow for physical limitations of chemical inks, different paper surfaces or other environmental factors that effect the final print job. The formulas do work accurately for your monitor ONLY!

On my screen I see a bright blue color, but according to the formula conversion, it will take full cyan and full magenta to achieve that color of blue. Full cyan and magenta make purple, not bright blue! There is downloadable color management software and other tools that can be purchased, or some can be found at no or low cost, that can tell you the amount of CMYK percentages you are using in a color. With practice, and a bit of tweaking, you can design using the CMYK color spectrum and get very close to the RGB results you are looking for. Some software programs have settings you can use to force the CMYK color spectrum colors as the only choices available to you as a designer. The most popular and widely accepted set of color values in the CMYK spectrum are PMS colors. Pantone colors are a set of colors that restrict you to tested color conversions and the color choices stop at realistic limits. Using Pantone's keeps you from choosing colors that will shift un-predictably. Using straight CMYK color values in the final output file eliminates any confusion, or conversion issues.

Start your color choices using the PMS values/charts, then convert those values to CMYK. Proof your work as you go. After a bit of practice, you can adjust your RGB color choices, too. If you choose a color, or one is chosen for you that falls outside of the CMYK spectrum, you will know simply by the high RGB values. Knowing these tricks and tips can help avoid a scenario where it looked great on the monitor (and desktop printer), but shifted to something less desirable on a commercial print job. If possible, use the same viewer or a trusted viewer to proof your work!

Commercial printers use different mixtures of color inks and grey to achieve their process colors! Ink is expensive and most commercial printers use percentages of grey in their colored inks to offset the cost. The commercial printer will find a percentage that doesn't really effect the final color too much, but allows the added grey(Black) ink (Usually cheaper in price) to reduce the demand on the full color. I don't mean that they pour black ink onto the mix, it's rather that the press software will substitute grey. (Ex. Full cyan can be set at 85% cyan and 15% grey). This is why even PMS colors can appear different from one commercial printer to another.

Modern commercial printing machines allow print company technicians through available PLC/CMS software to tweak and monitor (and some are monitored by the software and sensors) a printing job during the actual printing process. Scanning equipment may be used to scan color bars which tell the press software if the color is within tolerance, or needs adjustment and does this on the fly.

One final note on 4 color process printing. When you choose black, use the CMYK (0,0,0,100) value for Black.
If you use anything else, you risk overprint color problems where each color separation, prints it's part to make black, but doesn't align (Register) perfectly, so the end result is a little bit of color from each showing through at it's full value at the edges of the graphic.

Cut lines and Bleed?

When you design for commercial printing, you must also allow for the true size of the paper being printed on, not just the final output dimensions. In order to achieve edge to edge colors, even the commercial printers have to fake it. Just like your desktop (Or most desktop) printer, you have that edge that the machine uses to safely stop spraying ink during the print process, which leaves the the white unprinted border around the edges and sometimes a good 1/2" on the bottom of the page, if it didn't do this, the rollers and other parts of the printer would have ink on them and transfer that ink to the next piece of paper.

Commercial printers use paper that is larger than the final output and then trim or cut the excess paper or material to achieve the correct dimensions. Based on the printer itself and the cutting press used, things tend to move ever so slightly. Due to this movement and oversized paper or material, you need to design with this in mind. Most companies will provide templates or at least a set of instructions that inform you of these tolerances. The cut line is estimated, so colors for backgrounds and other parts of your design that need to go to the cut edge, should actually bleed or go to the full edge of the design. Inside the cut line is the safe line or zone. This area is where you can count on things not being cut off. Most templates or instructions will tell you in inches what these tolerances are. (Ex. Imprint dimensions: 2.1" x 3.6" at 350 dpi with 1/16" cut, 1/16" safe, and colors bleed to the edge.)

In conclusion:

Learn about colors and how/why you see them the way you do.
Set up your design station to match the commercial printer you're using as close as possible.
Follow the design templates/instructions.
Print proofs at actual print sizes if possible.
......More to come, keep checking back!!