As a graphic designer you are often designing work for both print media and screen/web devices. Working for the screen you stay in RGB mode, have the maximum colour gamut, can use low-resolution images and everything still looks great! Ink on paper is more restricted. The overriding principle is that you want to know what the image will look like before it is printed. Onscreen, you are adding different colours of light (Red, Green and Blue) together; things get brighter, but you can tone them down. On the page you are adding different colours of pigment (Cyan, Magenta, Yellow and Key (blacK)) together; things get darker and stay that way. The simple fact is that there are bright, vibrant colours achievable on the computer screen but not reproducible on paper. As a designer, then, the first decision is based on the eventual use of the artwork.
RGB vs CMYK
Paper-based work is best served by using CMYK mode in your design software. You will only have colours available to you that you can actually print. So it’s settled. Not quite – the paper is also limiting. Think about the futility of hoping to get bright, magazine-quality images on newsprint. You will not even be able get anything resembling white. The limitations of your medium must be dealt with. This is where colour profiles come in. When you know both the paper and ink being used, you can find the best colour profile to use within your software. It is a good idea to download all the latest profiles. The correct profile, along with a properly calibrated monitor can very closely give you that desired “what you see is what you get” match between screen and paper. Without a good profile, red will still appear red, but it will almost certainly appear different, often either darker or paler. This is especially important when using a corporate colour. That colour has exact specifications and needs to be reproduced almost exactly every time. In this case you need to print with more than just four ink colours. A predetermined spot colour can be formulated which will always match. Check with your printer if you require this.
If your design is to be used on the web and in print there is an additional option: design in RGB mode and then save a copy in CMYK, hopefully using the best profile. Surprises are possible when with the decreased gamut of CMYK. For example, a very bright picture of a billowy fabric contains a lot of subtlety in the image. When shifting down into the CYMK gamut many of the tones can become squeezed together and the image becomes flat (think of saving a full colour, 24-bit image in 16 colour mode – subtlety goes out the window). You could darken the fabric so that less compression occurs. The absolute colour gets changed but the texture is retained. This is one of those times where your human judgement is required to balance the trade-off. A related problem can be a “banding” effect in gradient shaded areas. If you do need to adjust the gamut, spot colours will stay the same. In a different web/paper setting it may be necessary to make your design as bright as possible and tone it down a little for the screen. Although pigment makes a darker image than does light, a printed solid black ink area usually comes out only as dark grey. A good solution is to make a rich black by changing the “recipe” of black: C(40%), M(20%), Y(35%), K(100%).
Top tips to keep your printer happy
Resolution
- Your screen has a lot lower resolution than what you print
- Screen, 72 dpi (dots per inch) vs. offset printing, usually 300 dpi minimum.
- A 21” diagonal screen displays the same amount of picture as a 5” diagonal printed piece.
- Simply “blowing up” a low resolution screen image to paper gives very poor images.
- If you know the number of pixels high and wide an image is, divide each by 300. Print it as that many inches, or less.
- Beware almost vertical or almost horizontal lines – these can produce a jagged “step” effect. Create a higher resolution image if you can.
- The resolution of vector graphics (Illustrator) is not a problem because they are redrawn with full detail each time they are scaled and rendered.
- Images shrink from screen to paper. Small text or intricate images will print with a quarter as high as on the screen. Will yours still be legible?
Edges
- The edges of your print are important. Slight variances in processes mean the paper might not be cut exactly of the cutline.
- On a small piece, such as a business card, there should be no text or graphics within 1/8” of the edge. This is the margin type safety (border).
- Larger pieces require larger borders.
- If your image has a background wash or design, extend it 1/8” past the cutline. This is the bleed.
- A magazine or poster, where you print right to the paper edge also needs a bleed. It eliminates a possible white border.
Font Problems
- When using older software, text creates special problems when moving from the screen to paper, depending on the font used.
- Using Adobe Open Type Fonts should keep everything looking good.
- Converting text to outlines removes the need for fonts but you lose editability.
File Formats
- If you are submitting any files other than PDFs, send a PDF proof file as a reference.
- Compress the files before sending them electronically. For PC use ZIP. For Mac OS X 10.3 Panther use File – Create Archive menu in the Finder.
- Something as simple as using standard three character file extensions to eliminate ambiguity can save a lot of trouble and delay.
- Your print shop should have on its website the acceptable and unacceptable file formats.
Submitting your file(s)
- Make sure you check with your shop on their acceptable methods of submission.
- Putting you file on a DVD and sending it to the shop allows you to also provide a hardcopy proof.
- Does the shop prefer receiving your file as an email attachment? If so what is the maximum file size? Some have a 2MB limit.
- Is there an online file upload service to the shop’s server?
- If the shop uses FTPs, the server name, login and password need to be obtained.
- Don’t forget to send all files needed, including fonts and links.
- It seems obvious, but make a backup of your files. Funny things happen at the end of a job.
- Long before your deadline, find out from the website how long your print job will take.
This list is a good start to building a great working relationship with your print provider. It is likely to make your jobs flow a bit easier through the system, thus helping with turnaround.