Difference between digital and litho printing
Digital is more suitable for shorter runs and Litho for longer runs.
Digital printing will print one complete copy of the file at a time whereas Litho Printing will produce the required number of copies from Page 1, then Page 2 and so on. The pages will then be collated [sorted into order] afterwards away from the Press.
Litho printing requires an intermediate, such as a plate, whereas Digital prints direct from the file to the machine and each copy comes off the machine collated..
Digital set ups are generally quicker and more simple than Litho setups which are more complex and take longer.
Weight of Stock:
In general, most Digital machines will run on stock weights between 70 gsm and 300 [sometimes 350] gsm. Offset presses will run onto both lighter weights and heavier weights.
Type of stock:
Digital machines are generally more limited in the types of stock onto which they can print although the ranges are increasing all the time. It is still safe to say however that the ranges of stock for Litho presses are still wider and generally cheaper if selecting a specialist stock. Some digital presses also do not image particularly well onto stocks which have had a finish applied to their surface e.g Laid.
Run length [number of prints per image]:
For full colour printing Digital presses are more suitable for the shorter run lengths, generally from 1 up to around 500 although this last figure may vary depending on the particular job requirements.
If you are printing in only one colour black, then this figure of 500 will increase considerably.
Turnround:
It is generally accepted that Digital printing is faster than Litho printing since no complicated setups are required nor is there a need to make plates.
Quality:
Historically, it has been said that Litho printing produces the best quality and that is still true today. However, Digital printing quality is now so good that to the average layman, in most cases it is hard for them to tell the difference, if not impossible. The use of graduated tints and large solid blocks of colour would tend to lead to Litho being selected as the preferred process however.
Price:
See Run Length above. Digital is generally less expensive for the shorter runs and Litho for the longer runs. Prices reduce significantly for the very long runs.
Range of colours:
If a number of specific spot [Pantone] colours are required to a high level of accuracy, then it may be best to specify Litho printing although Digital presses are now very good at matching some Pantone colours.
Original Image Quality:
Digital is slightly more forgiving in that it will produce good quality from images as low as 150dpi. Litho needs considerably more resolution.
Overprinting:
If you have a requirement to overprint your material after we have produced it using the digital process, say on a home laser printer, please be careful since some machines will melt some of the image that we have produced as it goes through your printer. Litho produced prints are generally more tolerant of subsequent over-printing.
Personalisation [Variable data]:
This makes each print a unique print and as such is most suited to Digital printing. The use of this service will considerably increase the return on investment and response rate for mailing campaigns compared with the shotgun approach.
Metallic Inks:
If you require Gold or Silver for example then this is best done using Litho Printing.
UV varnishing:
This will also generally lead to the Litho Printing process being selected.
Talk
Things they told us to look out for when sending work to the printers
- No bleed on documents, 3mm bleed and crop marks needed.
- Individual business cards needs to on individual sheets as opposed to eight on a single sheet.
- Brochures, booklets sent as spreads, they need to be sent as individual sheets so that they can organise them in the correct order for the printer.
- Front cover art needs to be sent separately, as PDF and original document format.
- Don't use spot colours with transparencies, instead send as overprint
- Keep image size to 300 dpi and the image size the actual size it'll be printed off as
Example of work they have printed
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