Whoa here. Most of the time I agree with, but this time I have to strongly disagree. You didn't really mean what you wrote here did you. If you did that is sure to give the wrong impression as maintaining correct color on digital output devices is just not that simple.
After almost 20 years of running digital output devices there are not enough fingers and toes of the people logged in here to count the number of times I have seen colors shift because of, changes to hardware both inkjet, (heads replaced, firmware changes, yes and even new ink cartridges, etc.) and toner devices, (drums. transfer belts, 2ndBTRs etc.). And media is an even worse culprit, from one roll to another or within a roll, and sheet feed paper, don't even get me started on that. Then another variable is temperature and humidity.
Well perhaps I as less than clear.
I work almost exclusively in large format inkjet, so I tend to think in those terms, and write in those terms.
So yes, if you widen "digital output devices" to include CLC machines, then yes, they are notoriously unstable.
But I was referring specifically to inkjet.
And, with regard to inkjet, my own experience -- which is fairly substantial -- covering all manner of inkjet devices, processes and media around the world, is that the process is remarkably stable, and much more stable than a lot of what you read on the Internet would lead you to believe.
In fact, my experience is that most aqueous, solvent, and UV machines tend to never drift at all unless there is a change to their ink, or to their head voltage.
Latex is another issue, and interestingly, all of the machines I've gotten calls on over the years that have had drift issues have been HP machines. After an issue I just worked through I'm working up an opinion on that, but I'll keep it to myself for now.
And just by the way, I'd honestly love it if this wasn't true, and these machines were as unstable as many are led to believe.
When I got into this business ten years ago, I assumed all I read out there was true, and that I'd have a ton of repeat business doing color tune-ups and the like. And it's turned out not to be true.
Most of the clients I have, and most of the profiles I write, they run them till they get rid of the machines. They'll get new machines and call me in to profile them, and I'll test the old ones, and it amazes me how little they move in how long a period of time.
I'd also just add that as far as I'm concerned any machine manufacturer that would invalidate existing machine printing conditions with a firmware update ought to be run right out if the industry. I've heard if that happening with HP, although I've never actually seen it myself. But anyone else? No. Never have.
What I have seen many, many, many times over the years is color workflow issues that have been wrongly blamed on machine drift. So while you do learn in this business never to say never, and while I'm not going to argue with you or anyone else over your own experiences, all I can tell you is that my own personal experiences are exactly as I describe.
