The print production manual
Kirsty Alderson
Contents.
1. Prtining processes 2. Colour systems 3. Colour gamut 4. RGB & CMYK colour models 5. Pantone matching system 6. Stock considerations 7. Proofing 8. Print finishes 9. Format & costing 10. Linen testers & registration
All images in this booklet have been sourced from google images.
Printing processes. Offset lithography. Etched aluminium plates that are wraooed around a cylinder transfer ink to an ‘offset’ rubber blanket roller and then to the print surface. Either fed on a sheet or from a roll using a ‘web’ offset machine. Commonly used for printing newspapers, magazines, brochures, stationery and books. Overall this is one of the most common ways of creating printed matter. This process creates high quality images. Rotogravure. Copper plates (with a mirror image) transfer ink directly to the print surface, usually on rolls. The plates are more durable so are better for long print runs. Commonly used for newspapers, magazines, postcards and corrugated cardboard packaging. Flexography. A positive, mirror image rubber polymer plate, on a cylinder, transfers ‘sticky’ ink directly to the print surface. Usually this process is roll fed. The image is usually raised off the plate by 2-4mm. The process is commonly used for corrugated boxes, shopping bags, food bags, milk and beverage cartons, flexiable plastics, self adhesive lables, disposable cups, envelopes and wallpaper. Digital printing. The reproduction of images from a computer to a material without physical process. Best for short runs on a range of print media. Screen printing. A print technique that uses woven mesh to create an ink blocking stencil. This process is both a hands on one and also it can be machine operated. It tends to be used more for one off designs and is commonly used for t-shirts as well as paper based media. Pad printing. This process is used to transfer a 2D image onto a 3D object via a ‘pad’. Its commonly used for branding objects such as pens, flasks, keyrings and memory sticks.
Colour systems. CMYK. (Cyan, magenta, yellow and key black) This is a four colour process that is subtractive. Its typically used in the most common printing process, offset lithography. RGB. (Red, green and blue) This is a screen based colour model that is additive. Red, green and blue light is added together to produce an array of colours. Greyscale. Black and white continous tone and any shade of grey, such as a black and white photo. Duotone. A continuous tone image that is printed in two or more spot colours. Spot colour. One or more specifically mixed colours as a result of a CMYK or RGB mix. Monochrome. Similar to greyscale but with coloured ink. One colour plus a percentage tints of that colour. Halftone. The mechanical process for converting tonal values into a series of dots that when printed give the impression of continuous tone.
Colour gamut. All screen devices work within their own colour gamut. None of them can reproduce the total range of colours seen by the human eye. No two devices have the same colour options because although they all use RGB, they interpret it differently. Whenever an image is moved from one device to another with different colour options the image colours will change to suit that particular devices gamut. Due to the fact each device has different colour space it is impossible for RGB colours seen on screen to match the printers CMYK colour space. This means that when a document is printed it will look considerably different to what you are viewing on screen depending on the colours you have chosen. You can see how your document will change in programmes such as photoshop by converting it to CMYK from RGB.
RGB & CMYK colour models. A colour model is an orderly system for creating a whole range of colours from a small set of primary colours. Colours percieved in additive colour models are a result of transmitted light. Colours percieved in subtractive models are the result of reflected light. Notice that the RGB model produces white in the middle where as the CMYK produces black. This is because when colours are printed one on top of the other they soak the paper which becomes darker. The colour models also represent the limitations that print actually has because you can’t really gain these really bright colours due to the fact layered ink gets darker. This is because the more ink that is added, the less light is reflected. Computers generally display RGB using 24 bit colour. There are 256 variations for each of the additive colours of red, green and blue, therefor there are 16, 777, 216 possible colours for RGB. There are more colour options for design for screen because of this. Important; ALWAYS use RGB for screen and CMYK for print.
Pantone matching system. The pantone matching system is a standardized colour reproduction system. By standardizing the colours, printers can refer to the colour matching system in different locations without direct contact with a client. Pantone colours can be described by their allocated number as each is different, which means all the designer needs to do is give the printer this number. All the pantone colour books are found in the designers software and then the printer has actual hard copies of these books. The books are all printed so that the colours can be found how they would look when printed on different stocks eg. pantone solid coated, for coated paper.
Stock considerations. When considering the stock for a project you will have a budget and the aim is to achieve the highest quality design whilst staying within this budget. The stock will effect the perception of a project and the colour may be altered. There is also the weight of the stock to be considered as this can effect elements such as the folding if it’s too heavy. The weight of a stock depends on what has been designed and it’s always a good idea to view previous examples of work on the stock you are considering. Examples of different stock... Coated paper. Paper with a coating applied to one or both sides. Avaliable in gloss, silk and matt. Coated papers are used for projects requiring a fine finish so are sometimes referred to as art paper. It generally produces sharper, brighter images. Commonly used to print brochures, leaflets and posters. Uncoated paper. This has no coating at all. Uncoated paper is avaliable in many different colours, weights and finishes and is more absorbent than coated paper. Commonly used for business stationery in laser printers. Wove. Paper made on a closely woven wire roller or mold that has a faint mesh pattern. Commonly used for stationery and book publishing. It’s a premium quality paper. Laid. Premium quality paper with a textured pattern of parallel lines, similar to hand made paper. Commonly used for business stationery. Bond. An economic, uncoated wove paper, often used for copying or laser printers.
Other... Weight of paper. Specified in GSM ‘grams per sqaure meter’ this is the thickness of the stock. For example, photocopier paper is 80gsm, good letterhead paper is 120gsm and a postcard is 300gsm.
Paper sizes. SRA papersize is used by commercial printing companies. It’s slightly larger than the A series to provide room for grip, trim and bleed. These paper sheets will after printing and binding be cut to match the A format. A0 - 841 x 1189mm A1 - 594 x 841mm A2 - 420 x 594mm A3 - 297 x 420mm A4 - 210 x 297mm A5 - 148 x 210mm A6 - 105 - 148mm SRA0 - 900 x 1280mm SRA1 - 640 x 900mm SRA2 - 450 X 640mm SRA3 - 320 x 450mm SRA4 - 225 x 320mm Bleed. This prevents unwanted white borders around the edges of a print. It adds an additional 3mm to the border of a page.
Proofing.
All graphic design work needs to be proofed before it can be sent to print. This is to check for any mistakes, see if the client is happy with the design and also see if the client would like anything changing. The proof is usually a hardcopy printout of the design and once the client is happy they sign it, if they want to make changes they can also mark on here what they would like changing. Once the proof has been signed it can go to print. This signature in a sense now lets the designer ‘off the hook’ because once printed, if mistakes are found on the design, the designer can say the design has been proofed by the client so this is not the fault of the designer.
Print finishes. Lamination and varnishing are used extensively in the print finishing of brochures as they give a feeling of quality to a publication. Lamination. You can’t always see the laminate but you can feel it as it creates a smooth finish. This will be matt laminate. Gloss laminate is easier seen and adds to the tactile quality of the page. Often this process is only used on brochures as it can add to the cost considerably. UV varnishing. This gives a similar effect to lamination although this process is better when printing a spot colour. It’s more beneficial as it’s cheaper and can be printed onto certain sections of a page such as the logo. Metallic inks. Again this is something that is spot printed. The inks have a reflective quality and are avaliable in a range of pantone colours. Hexachrome colours. Using six inks instead of four the colour spectrum can be extended on a print job. Foil blocking. Metallic foil is applied to a page using heat and pressure to create a reflective area. This effect has greater impact than metallic ink as it’s more reflective and sits on top of the paper. The downside is, it’s quite expensive and will often be carried out in a specialised workshop. Embossing. The technique of raising up a portion of a design in any desired shape. Another process which can add significantly to the cost. Debossing. The embossing process but reversed, pushing in a portion of a design. Die cutting. A metal tool punches into a piece of artwork to create an irregular shape on card or paper. A die cutter is often used to create packaging from a regular sheet but can also be used to cut out areas of things like brochures. Due to the fact the metal tool is sometimes made specially, it can again, add significantly to the cost.
Format & costing. Format and costing link quite well together because the format can have quite a big impact on the cost. If a design is large format it will obviously cost more because more ink will be used to cover the design and the stock will be large. However, the shape/format of the design itself may also effect the cost because if it’s a certain ‘awkward’ shape you may be limited to how many designs you can fit on the stock meaning you may need greater quantities of stock and the job may take longer. Other factors that effect costing... Colours. Limiting the number of colours you have on a design will make the print job cheaper because your using less inks. Paper choice. Papers that have higher substance are more expensive eg. special stocks with a particular finish. Print volume. Less prints will be more expensive because the printer takes time to set your job up so get as much out of it as you can. Printers tend to give discounts for bulk prints so this tends to be cheaper. Finishing. Special finishes and styles such as embossing and foiling add quite a lot to the cost so consider what is nescessary. Turnaround time. If you work ahead of your deadline there is less chance of you making mistakes because mistakes cost money. You have more time to make sure everything is up to standard.
Linen testers & registration. Both of these elements link together because they both relate to the quality of the final set of prints that are produced. In colour printing registration is the method of overlapping colours on one single image. There are different styles of registration, many of which use the alignment of specific marks. For example, lithography uses registration marks known as ‘T-BAR’. Using small registration marks on both the stone and paper. The printer measures the exact size of the paper and chosen margains. Then marks are made at both ends of the paper and also on the stone in the shape of a ‘T’. The printer matches the marks on the paper to those on the stone, this way the colours will be in-line. Programmes such as photoshop use bulls eyes and star targets for the alignment of artwork created on this programme.
Linen tester. A linen tester is used once a design has been printed to see how well the design has aligned and also take a look at the general quality of a piece of design work. A linen tester is a small magnifying device that allows us to view the design work up close and see the finer details. With CMYK printed design it allows us to see the induvidual dots and layering of the seperate colours ever so slightly.