Supplying Artwork

On this page we have put together some explanations of the common processes involved in producing artwork that is "Print Ready". We hope this will provide you with a good understanding and reduce the possibility for errors, allowing your job to be produced as efficiently and cost effective as possible.

General

One of the most useful things you can do to give us the best understanding of what you want your completed job to resemble, is to provide us with either a made up dummy, a previous copy or a sample of another job that you wish to match. A dummy can be produced on any standard laser/deskjet printer as the print quality and colours are not important at this stage. All you have to do is print out the artwork that you have on your computer and if possible fold it accordingly. Along with the dummy you could also provide us with other details such as quantity, specific pantone colours, size, folding, binding, proofing requirements and delivery.

If you are unsure about any of this our studio department will always be happy to help and talk you through the process. We can also provide you with low resolution proofs which can be made up as a dummy to give you an idea of what the final product will look like. If required we can also provide high resolution proofs or even a wet proof where we actually print a proof of the job on the printing press. High resolution and wet proofs are more for checking colour as apposed to a low resolution proof which is mainly used for page layouts and content checks.

Colour

Do not rely on the colours you see on your screen. Most monitors and desktop printers are not accurately calibrated and colours are likely to look different when printed on paper. Try to choose spot colours or CMYK tint mixes from sample swatches printed on coated or uncoated paper as appropriate. It is normally sensible to see some sort of colour proof - there is a range of options available to suit different requirements for price and fidelity. The industry standard for printed swatched as those made by the Pantone® company. Ensure that all colour images are converted from RGB or Indexed Colour modes to CMYK. Bright RGB colours are likely to look much duller when converted to the nearest printable equivalent. You must ensure that all colours that are to be printed in CMYK process colour are specifically designated as process separated (note that colours defined with the CMYK model will not automatically be process separated). If the colours are not designated as process separated incorrect spot colour plates will be generated. When using spot colours and dutones you should ensure that the names of colours in duotone or EPS files are correctly specified and imported into the page layout package. File you were to call a duotone black 'Process Black' or 'Process Blue' rather than 'Black' or 'Cyan' - 'Process Black' will output to a separate plate from the standard 'Black' in a page layout file.

Duotones usually need to be saved in EPS format to work. Duotone effects can be simulated by colourising TIFF files in page layout programs; however, the results are not as controllable as true duotones. If you are mixing spot colour tints such as in a duotone, you should ensure that the colours print at different screen angles. Colours usually all print at 45 degrees, which causes ugly screen-clash.

RGB vs CMYK

As we all know from playing with prisms or being surprised by a rainbow, the light we usually assume is colourless is really not. White light is made up by adding together all the colours–violet, blue, green, yellow, orange and red. A sensitive eye could theoretically perceive as many as 10 million different colours. However, since our eye has three basic kind of receptors, psychologically, we perceive three basic broad bands: red, green, and blue, We call these the three primary colours of light, know them best as the colours of our PC or Mac monitors, and refer to them by their initials, RGB. In the graphic arts, we separate the colours of light by using filters to screen out light of a particular colour. If we use a red filter, we subtract the red light; what remains is a combination of blue and green, which we call cyan. Similarly, if we subtract green with a green filter, the resulting colour, a combination of red and blue, is magenta. And, hard as it may be to imagine, using a blue filter will leave red and green light to combine, with a result of yellow. The colours resulting from this process of subtraction—cyan, magenta, and yellow—are the primary colours of ink. If the subtraction process were perfect, the result of combining all three of these colours would be a total absence of light-i.e., black-but it is not, and the result is rather brownish. So printers add a fourth colour, a true, robust black, to create a greater range of contrasts and deeper shadows. Full-colour printing, therefore, is CMYK-Cyan, Magenta, Yellow, and Black. The black printing ink is designated K to avoid confusion with B for blue.

Designers who create a file on their computer monitor in living colour are often surprised and sometimes disappointed by the look of their printed work. They should keep in mind that the colour on their screen is RGB, additive colours created by combinations of transparent light. The printed work is quite different, almost an opposite. It will be CMYK, the ink visible not as a light source but as a reflection. Each colour is applied separately, from its own press cylinder, to the paper. Full colour is achieved by laying down four colours, one on top of another. Each one of the four represents the part of the light that remained after filters subtracted all but one of light's primary colours. Additive vs. subtractive colour: one of the reasons graphic artists and designers are always in pursuit of depth and fire, remembering an elusive glow, always trying to push printers' envelopes. Four-colour process, marvelous as it is, can never be all colours to everyone.

Designing for CMYK printing

In order to print properly, any image files that you supply for CMYK printing must be in CMYK mode. RGB files will look good on screen, and they will even look good when printed on many of the desktop colour printers on the market today. However, they will not separate properly when made into film, and the resulting full printing job will not look the way you expect it to look.

Inexperienced graphic designers, unfamiliar with the limitations of the CMYK gamut, often provide a steady stream of RGB files, which we relentlessly convert to CMYK mode before sending for film output. Much of the time, the colour change that occurs is slight. Every once in a while, though, we get artwork whose effectiveness is severely compromised when the colour range is compressed during the transition to CMYK mode. It is often a challenging task to explain to the designer why there is absolutely no way to get that blue using CMYK, no matter how much we want to.

Most Tiff, JPG, GIF image files (called Bitmaps) generated by a scanner or camera are likely to be 24bit RGB format. Applications such as Adobe PhotoShop or Corel PhotoPaint have the ability to convert them.

When working in your graphic design software, you should leave your colour files in RGB mode up until you need to print separations, or until you need to know CMYK ink values, so you can match colours in another program. Don't make repeated changes between RGB and CMYK mode, using the mode menu. Every time you switch, a little clarity is lost. One switch is no problem; 20 switches makes a difference.

You may ask, why not simply switch to CMYK mode as soon as possible?

1. RGB files are 25% smaller, and are therefore 25% faster to work with and easier to store.
2. The CMYK gamut is pretty small. If you ever want to reproduce those files for a different medium (such as the web), you'll have thrown away some potentially useful information .
3. Some filters only work in RGB mode.

Trapping

Trapping printed colours by creating fractional overlaps is important for producing good print. QuarkXPress has automatic trapping which is generally satisfactory; notable exceptions to look out for are that it automatically sets solid black boxes to 'overprint' (which is not usually desirable where there is variable colour underneath) and that if even a small corner of a text box overlays an imported graphic coloured text may be trapped as if it also overlays the graphic (this may cause some text to look 'fatter' than it should).

These problems can be solved by customising the trapping. Page layout programs will not trap imported vector graphics, but you can apply trapping from within the illustration program; small black text should normally be set to overprint and areas of colour can be trapped using thin overprinting strokes.

Graphic files

It is important that you always supply the original graphic files placed in page layout documents. This should be done even if they are 'embedded' in a program like InDesign as embedded images are often stored incorrectly and cannot be edited.

Do not re-name linked graphic files once they have been placed. Never re-name or separate the individual parts of a DCS file, or re-name low resolution place-holder files supplied to you.

Use only TIFF or EPS formats for publishing, do not use GIF, JPEG, PICT or other formats. Do not use JPEG compression within EPS files (except DCS). It is advantageous to use compression for line art/bitmap TIFF files but with colour or grayscale images compression usually creates unacceptable delays for relatively little space advantage. In QuarkXpress 3.32 or earlier never apply a background of 'none' to a grayscale or colour TIFF file (it's OK for bitmap/line art) as Xpress is likely to generate ugly jagged edges while attempting to remove the background on the basis of a low resolution preview.

Scanning

Colour or grayscale images should ideally be scanned to a resolution of about 300dpi at the size they are used; 250dpi normally gives acceptable results, but below around 200dpi images will start to look soft and pixilated.

The quality of flatbed scanners has improved significantly but don't expect perfect reprographics quality colour scans from low or mid range scanners. Some practice flatbed scanners normally produce acceptable grayscale scans. For good printed results restrict grayscale levels to about 3-97 percent so that there are no large areas of pure black or white. Most monitors are unlikely to be accurately calibrated enough to make fine adjustments to scans - if in doubt measure actual percentage colour values. One way of improving all colour or grayscale scans is to apply an unsharp mask filter.

Simple black and white images should be scanned in 'line art' or 'bitmap' mode. Use a high resolution for these - ideally at least 600dpi at the size they are used, higher for images with fine detail.

Fonts

Layout (Bleed, Margins and Folding)

Always add bleed to images that run off the edge of a page. The 3mm standard should be strictly observed for books or booklets because the actual finished size of pages can vary significantly (the inner pages of a saddle stitched booklet can be several millimetres narrower than the cover). For posters, leaflets or stationery slightly less will normally be adequate.

Allow adequate margins. Very narrow margins look cramped and may even lead to text being trimmed off, particularly on booklets. Narrow borders (less than 4-5mm) may look uneven on a finished sheet if there is even slight variance in trimming.

The dynamics of manipulating paper at high speed mean that folds that seem possible in theory are not always practical on mechanical folders - you don't want to end up with 10,000 leaflets that can only be folded by hand. With many multi-panel folds it is necessary for some panels to be slightly narrower or wider than others - documents should be constructed to take account of this.

All this should be taken into account when designing your artwork. If you are unsure of anything and want advice please contact your account manager or sales on 029 2081 1020 and we will gladly guide you through.