Understanding the Differences Between Digital Printing and Offset Printing

[M�]

How do you distinguish digital printing from offset printing in a simple flayer/leaflet ?

Thx for your opinion.

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[jmendesign]

Interesting question that many may question my answer. I work pdf for offset exactly the same way as for digital printing - CMYK, 300 dpi with bleed. This always guarantees me the best result. This is if we are talking about professional digital printing. 

[M�]

I didn't express myself in correct English.
the question is: when I have in my hand a copy of a flyer or a brochure produced on 130 gram paper how can I recognize that it is a print made by laser/inkjet devices used in professional printing houses (in this sense I mean digital printing), or is it an offset print?

[jmendesign]

Maybe it was me who was too hasty in my response. @Mike Witherell  has the answer that seems correct to me, at least it is, also the away I use.

[Mike Witherell]

If you have a magnifying loupe, you can look closely. Many offset printing 4C jobs will show a halftone dot rosette pattern that is very regular. Digital printing devices can look more irregular. Digital printing toners are really finely milled synthetic resin plastic that gets melted onto the paper versus most commercial ink printing being dominated by soy-based ink. They smell different.

[M�]

grazie Mike,

you are suggesting the same tests that I did too.
not having a magnifying glass here with me, I used the magnification of the cell phone camera. I did not notice any substantial differences...
I tried to smell but I come from a week of cold... not smelling the typical odor of offset printing I thought it was laser/inkjet...

flyer

[Mike Witherell]

Another thought came to mind that shoud be mentioned: Much digital device printing employs stochastic screening and so when you look at it up close with a loupe, you will not see orderly dot rosettes, but seemingly random sputterings of ink. Stochastic is not really random, of course, but it is not trying to recreate halftone dot rosettes.

[Peter Spier]

Many higher end offset jobs are also printed with stochastic screens these days, too, so I wouldn't use that as the only criterion.

[M�]

probably fineart or similar, not a flyer.

...so I understand it is not so easy to rapidly understand the printing tecnique used.

wrong ?

[Peter Spier]

The screening used would depend on the RIP driving plate creation (or the digital press), not the work being printed, so its probably more likely the size of the run that would determine the method of printing than what the item is.

And yes, it can be pretty hard to detect the difference between a high-end digital print vs offset.

[M�]

certainly the number of copies needed determines the choice of offset versus digital.
however I thought that the choice of using a stochastic screen also depended on the difficulty of reproducing a certain effect or shade that could benefit from the type of screen used. 

[Peter Spier]

Perhaps in a very large shop there might be a variety of options for screening available, but in my experience it's "you use what you've got." When I was actively preparing work for clients my printer of choice had a 5-head Komori that handled only one side per pass, but everything they ran on it wasprobably conventionally screened at the time and it was all first rate. They printed fine art for museums and brochures for me. When he was forced to declare bankruptcy he hooked up with a larger printer with newer equipment (and higher costs and charges) and that output was all stochastic. Was it better in the photos? Hard to say since the previous work was also excellent.

Good printers take pride in their work and use the best tools they have avaialable. There would be no additional cost that I can imagine in producing plates using stocahstic screening so I would bet that would be the default if the RIP produces it.

[M�]

thx, you put my thoughts in order

[Jeffrey_Smith]

You can examine all content, text, graphics, solids, etc. with high magnification, and look for the clarity around edges for output resolution. Typically digital output devices use a dpi resolution less than platemaking devices used in offset printing. 300-600dpi for digital, 1200-2540dpi for offset

[Robert at ID-Tasker · Accepted solution]

Offset will be more dull than digital - especially in comparison to toner / wax. 

Digital won't be perfectly "flat" - toner / wax is melted on the surface of the paper. 

[M�]

I agree, this aspect is very useful in identifying the type of print