One of the most common questions we get is around the difference between offset and digital printing processes. The two processes are completely different, but are very common in the industry for different types of print jobs. This article should, hopefully, make it a little easier to understand.
Offset printing is a more traditional method that uses inks, or a mixture of them, to produce a printed image. The inks are transferred to the paper with our printing presses using plates, which repel and attract inks in just the right spot using a combination of water and alcohol. The presses take the ink, apply it to the plate, transfer it to a ‘blanket’ and then transfer that image to your sheet of paper.
Digital printing uses a dry powder known as toner, which is transferred to the sheet through a series of electrostatic charges, both positive and negative. By applying electric charge to a drum unit within the press, and then applying the opposite charge to that unit using a laser unit, toner is then drawn onto the drum in the precise location where an image should be printed. Four separate units go through this process, and the image from all four is then combined on a belt, which then transfers that toner on to sheets of paper. A fusing unit then heats the toner to just the right temperature so it instantaneously adheres to the sheet. Pretty tricky stuff, huh?
The biggest difference when it comes to both methods is the setup and drying time. Offset printed jobs can take 1-3 days to dry depending on the stock and the setup involved in creating plates is more time consuming than digital alternatives. Digital, on the other hand, has minimal set up time in comparison and the prints come out ready for immediate use (unless they need ‘finishing’, such as cutting to size or folding).
When quoting a job, digital is typically more cost effective for shorter runs. Offset is especially cost effective when you start talking in thousands of sheets.
With turnaround time, offset printing takes longer to setup and dry and since they’re larger runs, the finishing time (cutting to size, folding etc.) can increase. Digital prints don’t need to dry, the setup is much less involved, and the runs are usually smaller, making it a much quicker printing process.
Personalising prints, such as putting a different name on each print (like mail merge in MS Word) is only possible with digital. This is because the plates used in the offset printing process are a set image. If you had 100 names on your invitations, for example, you’d have to make 100 plates, which would be a very costly exercise. The exception to this however, is with numbering. Offset printing presses utilise numbering units to create products like invoice/docket books with unique, sequential numbering and barcoding.
Colour wise, offset presses have the advantage of being much truer to the common colour standard known as Pantone. You can choose the exact colour required in an offset print job and the ink will be mixed and matched to the standard. Digital is still very good at approximating colours but most digital presses lack special colours like fluorescents and metallics, which offset caters for if required.
Print Storm keeps up to date with the latest, high end printing equipment from Heidelberg and Fuji Xerox, allowing us to be competitive on price without sacrificing quality.
If you’re not sure whether your next jobs needs to be printed on a digital or offset machine, don’t hesitate to give us a call on 1800-2-PRINT.