When to go Digital?

Below is an extract from the research and practical experience of Martin Stern of Purbrooks limited and some information on the point at which offset litho and digital printing cross over so that best value and value for money can always be measured and assured. Purbrooks are a member of the British Printing Industries Federation (BPIF) and the BPIF teach and promote best practice.


There are two main reasons for choosing to print digitally: speed of turnaround and low cost on short runs.


The quick turnaround of digital print is due to the fact that the ink on toner-based machines dries instantly, even on uncoated stocks, so there is no delay in the printing process.


It is always best practice to have a hard copy proof, to ensure all colours are correct, and there are no problems in the PDF or using your chosen printing substrate or method.


This is because:
• the shade, colour, texture and reflection of paper, card, plastic, etc. varies with batches and processes.
• as toner/ink is Cyan, Magenta, Yellow and Black, (CMYK) and uses reflective light and some images on paper, card, plastic, etc. may limit contrast and look flat, dull or enhance contrast, colour or brilliance.
• as a screen view is projected light in Red, Green & Blue (RGB).
• A PDF may not have all the fonts embedded in the file, so the software may substitute another font.


The short run nature of digital jobs does allow the quicker option of approving just a PDF before printing, further speeding up the turnaround time, but is very hard to match a screen view with a hardcopy print view.


A digital press does not use printing plates and there is a much smaller machine make-ready time to charge out or recover.


Some software systems like Quite Imposing http://www.quite.com/imposing/ can cut down studio time for page imposition. This can be done on the fly or with templates, so there is less overhead to recover for design and bleeding layouts.


Unlike offset litho, a digital press often needs very few sheets of paper in the set-up process, which again is a clear saving that can be passed on to the customer. This means that on short runs digital can be a very cost-effective way of producing a job.


However, as the quantity increases, digital printing eventually becomes more expensive than litho due to the slower running speed and the “click charges” levied by the manufacturer of the press.


The precise point at which litho becomes cheaper depends on a number of factors within the specification of the job, primarily document size and pagination.


The graphs on this page illustrate the cross-over point for three projects and it can be seen that the quantity at which this occurs varies from 350 copies for a 8pp A4 to 1000 copies for 2pp A4.

Purbrooks are happy to advise on the most appropriate process for a particular project and can quote for both litho and digital to assist clients in deciding on the balance between quality, speed and price.


Purbrooks point out that it is important that the quality of finishing should be identical whatever the printing process as this will differentiate some printers’ finished digital printing from that of their competitors.


Reproduced and based on an article by kind permission of Martin Stern
Purbrooks.
Gresham Way, Wimbledon Park
London SW19 8ED
T: 020 8944 3200 F: 020 8944 3237
e: martin@purbrooks.co.uk
w: www.purbrooks.co.uk