How to choose digital or offset printing…

Posted at September 9, 2009

When embarking on your next print project, you will be faced with choosing either digital or offset printing. See the pros and cons of each process.

The Offset Printing Process
Offset lithography is the most commonly trusted, high volume commercial printing technology. In offset printing, the image is first burned onto a plate, and is then transferred (or offset) from the plate to a rubber sheet, and finally to the printing surface. The lithographic process is based on the repulsion of oil and water. The image to be printed gets ink from ink rollers, while the non printing area attracts a film of water, keeping the non printing areas ink-free. It often takes an hour or more to print a single page. Once up and running however, the economies and speed of offset printing for print runs over 750 pages typically will be better than digital processes.

The Digital Printing Process
If you have a desktop printer at home, you’re already familiar with the process of digital printing. Many of the steps required for offset printing are eliminated (ie, making films and color proofs, manually stripping the pieces together, and making plates), which results in a much more affordable print solution. Digital printing uses a different technology altogether. Images are produced with very fine toner. The time it takes to print the first page is usually well under a minute. This technology makes short runs, or runs from 1 to about 750 impressions less expensive, as well as quicker to produce than offset printing. Color digital presses use four-color process (CMYK) printing.

How to choose between digital or offset printing?
Quantity, timeframe, and quality are the deciding factors in whether to use offset printing or digital printing. Digital printing is used primarily when you need something very quickly or in very small quantities, but other factors, such as color, the need for variable printing, or sheet size may come into play as well.

Here is a table of comparisons between digital and offset printing that may help you make your decision…

	OFFSET	DIGITAL
Quantity	High quantities, 750+	Low quantities (short runs) less than 750
Color	Pantone® (PMS) or CMYK	CMYK
Turnaround	Not needed quickly	Need it quickly, short turnaround
Price	Prints higher quantities at much less cost	Prints lower quantities at much less cost
Quality	Higher image quality, higher resolution and no streaks/spots	High image quality not a factor
Consistency	Prints can vary from run to run	Every print is the same. More accurate counts, less waste and fewer variations, due to not having to balance ink and water during press run.
Sheet Size	Better options of printing larger sheets as long as you are doing more than a few of any item	Most digital presses only print up to a 14×20 sheet although 12 x18 is the most common sheet size
Variable Text	No	Can print variable text or images where each sheet off the press is unique in some personalized way (database driven, e.g. mailing lists, marketing materials, direct mail pieces, letters, etc. with a different name/address or number/code on each printed piece)
Finishing	Must dry or be coated before handling	Once a sheet is off a digital press it can be cut, folded or finished very quickly
Special Inks	Yes	No special inks (metallics, overglosses, fluorescents) since all colors will have to fall within a CMYK gamut
Stock/Printing Surfaces	Works on a wide range of printing surfaces including thick paper, wood, cloth, metal, leather, rough paper and plastic	Limited weights (thicknesses) and types of paper they’re able to print on
Proofing	If you need hard copy proofs, very accurate color proofing can become expensive	Offers more accurate proofs, since what you see is an actual sample of the printed piece, printed using the exact process as the intended run