How to handle the G7 compensation curve with scheduling of production

[Bloodsaler]

I have been bothered by this question for long.
Suppose we have 4 presses,each press has done a G7 test serprately,that means each press have its own compensation curve.
But our production schedule are full,so the real situation is we can`t manage all the jobs in a certain press,it may changed in some circumstance.That means we do our prepress for one press compensation curve,but suddenly this job need to move to another press,but the platemaking almost done.All we have to do is replatemaking another set of plates for the other press,but in this process,the time will be wasted.And it may delaying the delivery.
So I want to know guys,what you will do when you meet this situation?

[meddington]

Not many great options...either re-plate with custom curves, use a generic curve for all plates and deal with the inherent differences between the presses, or nail down scheduling so that you avoid last minute re-routing of jobs and do just-in-time plating. If the tonal differences between presses were different enough to warrant custom plate curves, then you have a trade off and have to look at what's costing you more money. Luckily with CTP the plating stage can go pretty quick.

[TerryWyse]

Been there....done that.....only I'm the guy making the G7 curves for a customer....and this problem comes up occasionally where they purposely have "identical" presses so they can exchange plates.

First thing, get all the presses printing identically as much as you can. Fix the mechanical issues first and then simply make sure that you're using all the same consumables (ink, blankets, fountain solution) and that each press crew is preparing the press IDENTICALLY in terms of chemistry, pressures, packing, etc.

If it were me being given this task, I'd run an initial calibration run (linear) on each press and see where they're all printing relative to each other. It's obviously important the same aimpoints be used when you do this (insert shameless plug for SpotOn! software here). Once you do that, you should have a good picture of what's going with each press relative to the others...or the average. If you see that 3 out of 4 are close, average those presses together and come up with a common curve. The one press that's out, either do a custom curve for that one press or simply note how this press prints relative to the others and see if you can fix it or use the common curve and accept the difference. Usually the average curve of 2 or more presses is close enough that a slight push/pull of the densities is all you need to get a reasonable match between them.

My (G)7 cents worth. :-)

Terry

[Bloodsaler]

Thanks guys,your advises I have considered,but doing all the presses calibrated need a long time,but during the calibration time,I may have to ensure the calibrated one printed great gray balance,and this conflict with production schedule~
I have no other great idea than yours,but some of my presses are komori,some are heidelberg,some are KBA,may make every press in a same condition harder?

[David Milisock]

Thanks guys,your advises I have considered,but doing all the presses calibrated need a long time,but during the calibration time,I may have to ensure the calibrated one printed great gray balance,and this conflict with production schedule~
I have no other great idea than yours,but some of my presses are komori,some are heidelberg,some are KBA,may make every press in a same condition harder?

Unfortunately no matter what calibration process you use the solution would be to invest some time into researching redundant and or a single faster plate setting solution. This is an expensive solution.

[tmiller_iluvprinting]

Unfortunately no matter what calibration process you use the solution would be to invest some time into researching redundant and or a single faster plate setting solution. This is an expensive solution.

Geez Dave-I don't see how a faster plate setter is going to help find harmony between presses from 3 different manufacturers. Are you sure you are answering the original post, or are you confused with another?

Regards,
Todd

[David Milisock]

Geez Dave-I don't see how a faster plate setter is going to help find harmony between presses from 3 different manufacturers. Are you sure you are answering the original post, or are you confused with another?

Regards,
Todd

No it's not but since there is no answer to that issue he can use faster or multiple plate setters andwait to plat euntilthe last moment.
The newer plate on demand systems may be of some asistance there btu as i said this could be big bucks

[tmiller_iluvprinting]

No it's not but since there is no answer to that issue he can use faster or multiple plate setters andwait to plat euntilthe last moment.
The newer plate on demand systems may be of some asistance there btu as i said this could be big bucks

There is an answer to the original question and Mike And Terry have more than covered it. I would like to suggest to you that we leave the advice to the true color management professionals, and to those that truly understand the world of print.
To the rest I say "Beware false prophets!"

Regards,
Todd

[David Milisock]

There is an answer to the original question and Mike And Terry have more than covered it. I would like to suggest to you that we leave the advice to the true color management professionals, and to those that truly understand the world of print.
To the rest I say "Beware false prophets!"

Regards,
Todd

No what he got was a bunch of his and that, curves that will vary as the press ages and one universal curve that won't last a month after it's made. Each press is different, plate at the last minute to the destinatiin press. Unfortunately this guy has to make money he'll spend more then he'll make on 20 jobs doning anything less. Used plate setters are getting cheaper right now.

Presses are fluid, a thoudsnd things vary and change that's why I lienerize and use PS management.

[meddington]

I've got plate curves that were created in 2005 and 2007 still in use and still valid. Just sayin'