Do Printers Believe in Continuous Improvement?

[danremaley]

I can tell you from being a consultant for GATF a number of years, that most printing companies have no budget for training. I was a process control consultant and found less than 5% of the printers have a process control system in place. Other issues are that they measure the wrong data at press (density instead of grey balance and dot gain).

[gordo]

I can tell you from being a consultant for GATF a number of years, that most printing companies have no budget for training.

Absolutely true.

I was a process control consultant and found less than 5% of the printers have a process control system in place.

Absolutely true.

Other issues are that they measure the wrong data at press (density instead of grey balance and dot gain).

Hmmmmm, no. Press operators measure density because that's the only real control they have. Measuring dot gain is useless and grey balance is problematic and for all practical purposes useless as a print production metric.

Best, gordo

[Green Printer]

Gordo you hit the nail on the head with density.

You can measure dot gain and gray balance all day the press operator must and will change density to achieve them. Running a job to a preset and tested density used in your shop should give you proper gray balance and correct dot gain. If you must stray from your normal density you have something physically wrong be it a consumable, press packing, operator error, ink water balance, wrong plate curve, plates exposure and what ever else can go wrong. Any time your density is out of range so is your process control.

[danremaley]

Absolutely true

Absolutely true.
Hmmmmm, no. Press operators measure density because that's the only real control they have. Measuring dot gain is useless and grey balance is problematic and for all practical purposes useless as a print production metric.
Best, gordo

Felix Brunner would take exception to your claims. He knows more about printing than you, me or anyone. . alive or dead! He controls color by measuring midtone dot gain and adjusting the density accordingly but the MEASUREMENT is gray balance. Don't be foolish follow the professionals!
Dan Remaley (external champion)
412.889.7643

[danremaley]

Simply not true. . .there's nothing WRONG. . dot gains change all day long and the relationship between Mag/Cyan gains change the gray balance and therefore color. The "secret" to color printing is keeping the dot gain relationship constant. I have a great printed reference that shows this example. go to System Brunner AG to learn more. I teach the pressman to measure the midtone gray with a densitometer, look at the 3-filter readings and adjust density until they're within .03 of each other - gray balance. I could teach you too! "google me".
Dan Remaley (external champion)
412.889.7643

[Erik Nikkanen]

I teach the pressman to measure the midtone gray with a densitometer, look at the 3-filter readings and adjust density until they're within .03 of each other - gray balance.

412.889.7643

How do the three filter readings relate to density control? I am curious how you view this.

[danremaley]

Hi Erik, we would increase or decrease density of Y-M-C to create a perfect gray from 50C/40M/40Y (the patch we read). Of course this is after the plate curves were made under a stable condition. see System Brunner AG for more information.
Dan Remaley
412.889.7643

[Erik Nikkanen]

Hi Erik, we would increase or decrease density of Y-M-C to create a perfect gray from 50C/40M/40Y (the patch we read). Of course this is after the plate curves were made under a stable condition. see System Brunner AG for more information.
Dan Remaley
412.889.7643

Dan, you didn't exactly answer the question as I intended. I will rephrase it a different way to be more specific.

Are you saying that in your example of the screened grey patch, that the measured Y density relates to the Y solid ink density and the same for the M density to the M solid ink density and the C density to the C solid ink density?

Is that how you understand it?

Thanks for the clarification.

[gordo]

Felix Brunner would take exception to your claims. He knows more about printing than you, me or anyone. . alive or dead! He controls color by measuring midtone dot gain and adjusting the density accordingly but the MEASUREMENT is gray balance. Don't be foolish follow the professionals!

I've used System Brunner at various times since the early 80s. It had application then (in the 80s) based on the technology used for separation, plate imaging, and press function at that time. However, the system is not as applicable today. If you do an unbiased testing of its principles you will quickly see that they have very limited value in today's production process.
At the present moment I'm on a ferry, but as soon as I reach landfall and get to my home I'll post an example of how these notions of grey balance fail.
In the meanwhile you can read this explanation of the reasons why on my blog:
The Print Guide: Grey Balance Unbalanced – An inconvenient truth

Best, gordo

[danremaley]

Dan, you didn't exactly answer the question as I intended. I will rephrase it a different way to be more specific.

Are you saying that in your example of the screened grey patch, that the measured Y density relates to the Y solid ink density and the same for the M density to the M solid ink density and the C density to the C solid ink density?

Is that how you understand it?

Thanks for the clarification.

Let's see if I can explain- equal amounts of R-G-B equal gray, so the measurement of Cyan(-R filter) Magenta(-G filter) Yelo (-B filter) in equal density value, (i.e. Y.58 M.58 C.58) equals gray. Color is made from both the density and size of the dot, since the pressman can't easily change the size of the dot he increases (or decreases) the density. Without any measuring instrument a pressman "visually" creates gray balance by eliminating any "casts" by increasing or decreasing density, to a point, after which, only new plates, with different dots, will be needed.
I have a great reference piece that shows this relationship, send me an e-mail and I'll return a pdf file.
Dan Remaley
412.889.7643