While the responsibility for accurate reproduction lies with the printer, a designer can contribute to the elimination of errors and mistakes by being aware of some of the common pitfalls that occur and by creating designs that accommodate them.
Printing a four colour job;
To print a simple four-colour card, the design needs to have a bleed so that once it is trimmed it will not have a white edge of unprinted stock. Normal design practice calls for a 3mm bleed, but more or less may be used depending on the job and the printing method used. For this reason, it is best to discuss the bleed of a job with the printer. Registration problems occur when the impressions the plates make on the stock are not quite aligned or in key. The K of CYMK stands for key as the other plates key into the master plate.
One-colour printing does not present colour registration problems as there is nothing for a printing plate to register with. Registration problems may occur as soon as more than one colour is printed. It may look slightly distorted or blurred due to mis-registration. A grey scale image will print fine as it is printed with just a black plate. In fact any single colour image printing from a single plate will all be fine as there is no registration needed.
Registration problems with reversed-out text are most acute with small text, particularly as mis-registration is most common on low quality print jobs such as newspapers. Mis-registration of small text can make it legible. Restricting reversed-out ext to one of the four process colours is the safest way to guarentee no registration problems, as only a single, flat colour will rint. Fine line work also poses problems for the same reason.
Bleed: The printing of a design over and beyond its trim marks.
Trim: The process of cutting away the waste stock around a design to form the final format once the job has been printed.
Registration: The exact alignment of two or more printed images with each other on the same stock.
Tip-ins and Tip-ons;
A tip-in is the attachment of a single page into a publication by wrapping it around the central fold of a section and glueing along the binding edge. If the tip-in is shorter than the publication it must be aligned to either the top or bottom edge. Fine art prints are sometimes printed intaglio and tipped-in.
A tip-on is when a page or other element, such as a reply card, is pasted into a publication. A tip-in can be located anywhere on the host page and may be of a temporary or a permanent nature.
ISO 216 "Writing paper and certain classes of printed matter; Trimmed sizes; A and B series" specifies international standard (ISO) paper sizes, used in most countries in the world today with three series of paper sizes: A, B and C. Series C is primarily used for envelopes.
By 1977 A4 was the standard letter format in 88 of 148 countries. Today the standard has been adopted by all countries in the world except the United States and Canada.
Many posters use B-series paper or a close approximation, such as 50 cm × 70 cm; B5 is a relatively common choice for books. The B series is also used for envelopes and passports. The B-series is widely used in the printing industry to describe both paper sizes and printing press sizes, including digital presses.
An A4 page will fit into a C4 envelope, A5 will fit into a C5 envelope and so on.
The practical usage of this is that a letter written on A4 paper fits inside a C4 envelope, and C4 paper fits inside a B4 envelope.