How do they do it?

[gordo]

Pantone is of course more interested in keeping their system LAB agnostic so that they can keep selling books with "Pantone 485" instead of everyone universally targeting the generic LAB coordinate of 49,67,53.

Imagine if medicine worked this way. We'd all be stuck buying Bayer Aspirin instead of acetylsalicylic acid.

I don't want to be an apologist for Pantone, however a recipe-based system is likely better than a Lab-based system. To use your medical analogy, when you go to your pharmasist to have your prescription filled, it is quite probable that they will use a recipe of base ingredients to create the final medicine that you buy.
A recipe based on qualified ingedients measured in parts, like Pantone colors, will likely be more accurate, and consistent than one based on Lab values which will when measured will vary from instument to instrument.

best, gordo

 

[Deleted member 16349]

I don't want to be an apologist for Pantone, however a recipe-based system is likely better than a Lab-based system. To use your medical analogy, when you go to your pharmasist to have your prescription filled, it is quite probable that they will use a recipe of base ingredients to create the final medicine that you buy.
A recipe based on qualified ingedients measured in parts, like Pantone colors, will likely be more accurate, and consistent than one based on Lab values which will when measured will vary from instument to instrument.

best, gordo

I think it is better for Pantone to use the recipe method to make their guides than for its end users.

Their recipes are not suitable for any other ink system than the Pantone inks printed on their paper stock on their printing process. And even with that method, there was some variation in their guides.

I worked for over three years in a company that printed on plastic cups using the dry offset method and with presses that had common blankets. These presses had up to eight ink fountains per press and there were almost 40 presses in one hall.

No process printing was done on these presses. All were spot inks that were required to be able to hit the Pantone colours. Each ink formula had to be custom made in house to match to the Pantone guide on the particular plastic used. We changed ink suppliers and it took over a year to confirm 75% of the new formulas that were required. And when new editions to the Pantone guide came out, we had to tweak some formulas to obtain the match to the slightly different colour in the new guide.

Having a Lab target in many ways is easier for a production requirement. It does not change from year to year as it can with Pantone guide colours.

 

[Cornishpastythighs]

Cornish, nice photos. I wish they would put dates on internet articles and press releases. Often there is nothing.

Also of interest, it looks to me like it is Dry Offset and not Waterless. It looks like a raised image area on the plate cylinder.

I think this press is dry offset and not a waterless(Toray) press

 

[gordo]

I think it is better for Pantone to use the recipe method to make their guides than for its end users.

Their recipes are not suitable for any other ink system than the Pantone inks printed on their paper stock on their printing process. And even with that method, there was some variation in their guides.

It's a proprietary system after all. Variation is still part of the process.

Having a Lab target in many ways is easier for a production requirement. It does not change from year to year as it can with Pantone guide colours.

Lab specified value targets can still cause deviation from the target color due to instrument variation.

When I had to deal with such issues I (or the CSR/sales rep) would try and clarify with the client exactly what their target for color was; Pantone's Lab values, our draw downs, their Pantone chip, a previously printed job, etc.

best, gordo

 

[Deleted member 16349]

It's a proprietary system after all. Variation is still part of the process.



Lab specified value targets can still cause deviation from the target color due to instrument variation.

When I had to deal with such issues I (or the CSR/sales rep) would try and clarify with the client exactly what their target for color was; Pantone's Lab values, our draw downs, their Pantone chip, a previously printed job, etc.

best, gordo

Gordon, I agree that colour issues are a messy business.

Colour science is not an exact science. The Standard Observer is an average of how people see colour. It is not an exact way that people see colour even under its rigid viewing conditions (1931).

But for practical purposes, we use the Standard Observer model and out of that comes Lab values. To say that one will have deviations using Lab targets because the instruments have variation and therefore one should not depend on Lab values is IMO a faulty logic.

There is an issue regarding instrument agreement but there is also an issue about instrument accuracy. Spectrophotometers that are used in the graphic arts are not highly accurate with regards to the colour calculation. Instruments in the hundreds of thousands of dollars are required to obtain more accurate readings. This is way outside the range of what printers could afford and practically it would not be necessary.

If one bases a matching system on visual results is this better? People see colour differently. This is called Observer Metamerism and I have read that this can have a variation of Delta 2 for people. So is Delta 2 better than the variation in what the instruments will read? I don't know for sure but it is something to think about when a group of people can not agree on the colour match.

Having a standard such as Lab to deal with colour matching is not perfect but it is at least a stake in the ground where potentially all can agree that if it measures the same it should be accepted. If one has variation in the instruments maybe better calibration is needed.

 

[chevalier]

Lab specified value targets can still cause deviation from the target color due to instrument variation.

Having a standard such as Lab to deal with colour matching is not perfect but it is at least a stake in the ground where potentially all can agree that if it measures the same it should be accepted. If one has variation in the instruments maybe better calibration is needed.

This is why we submit drawdowns and when approved scan them into the press with the scanner that also checks press sheets (same very expensive measuring instrument, same reading). With objectively measured data (within acceptable device variance) we can at least have something "real" to target rather than subjectivity of various human eyes.

 

[Cornishpastythighs]

Dont forget that 99.99% of our customers are not using high priced equipment to check for colour. They are relying on the visual match to the target they agreed upon (drawdowns PMS, signed standards etc). This could be in the form of a QA incoming inspection in a poorly lit warehouse or around a company boardroom. I believe it is up to us the printer to use the equipment to make sure what we are supplying to them is repeatable to the agreed targets. my 0.02 pence worth

 

[Deleted member 16349]

I believe it is up to us the printer to use the equipment to make sure what we are supplying to them is repeatable to the agreed targets. my 0.02 pence worth

Expectations of what can be done are sometimes higher than what is practical with respect to colour matching. Trying to do the best one can is a good aim. With colour, not everyone will be totally happy for valid and invalid reasons

I suspect that customers might be more concerned about variations within a run than with an exact match to a target. For the printer, what can one say if the customer puts samples of the print run on your desk and they look different.

One needs consistency before you can get better predictability.

 

[Cornishpastythighs]

Customers should expect both, colour on agreed target and variation within agreed standards. Not much point having minimal colour variation for a colour that doesnt match what the customer expects.

 

[gordo]

[snip]
If one bases a matching system on visual results is this better? People see colour differently. This is called Observer Metamerism and I have read that this can have a variation of Delta 2 for people. So is Delta 2 better than the variation in what the instruments will read? I don't know for sure but it is something to think about when a group of people can not agree on the colour match.

Having a standard such as Lab to deal with colour matching is not perfect but it is at least a stake in the ground where potentially all can agree that if it measures the same it should be accepted. If one has variation in the instruments maybe better calibration is needed.

At the 2007 Splash conference PIA/GATF presented the results of their tests of 7 different popular spectrophotometer brands - each properly calibrated to its supplied reference ceramic target. All units were set to the same illumination & observer angle (D50/ 2°) and with low reflectance black backing. Each print sample was measured three times under the same conditions and the results were the average of the three measurements.

They found that the instrument-to-instrument agreement could be off by as much as a delta E of 9 when measuring standard process colors.

So, potentially, using the example in this thread, I could compare the Lab value that Pantone publishes and measure the respective patch of color in my swatch book and see a delta E of 9 simply because of the brand of instrument that I was using.

If this was carpentry instead of printing, the tape measures would be made of rubber.

best gordo

 

[Deleted member 16349]

At the 2007 Splash conference PIA/GATF presented the results of their tests of 7 different popular spectrophotometer brands - each properly calibrated to its supplied reference ceramic target. All units were set to the same illumination & observer angle (D50/ 2°) and with low reflectance black backing. Each print sample was measured three times under the same conditions and the results were the average of the three measurements.

They found that the instrument-to-instrument agreement could be off by as much as a delta E of 9 when measuring standard process colors.

Good points. It confirms that instruments used in the graphic arts are not accurate. They don't agree with each other and therefore don't agree with the real colour value that one would have to measure using very expensive instruments at institutions. I am a bit surprised at the range of the delta E but that is what they found.

So much for the science in the industry. Great marketing hype by suppliers in the industry but not such a firm scientific foundation. Part of the value of having a scientific or theoretical view of things is that it helps one know how valid claims are and how practical proposed solutions can be.

So back to your Pantone point. Since there is poor capability of instruments to measure Lab values, then we are left with using a visual match method under proper conditions. So I might have to reluctantly agree with your earlier comments. Maybe that is the best option out of a messy situation. As an engineer, I am not so happy with this situation.

A side note about instruments. Older versions of densitometers that use filters might have less problems of agreement than newer versions that use spectral data to calculate the density values. This is due to the design of the instrument in how it divides up the spectral visual range.

 

[Cold]

I would not propose spec'ing Lab in this instance due to the above conversations regarding cross-instrumentation.

What I can hope for, is that some day Pantone implements their own internal Lab controls with a tolerancing of much less than the enormous variation that we see from one printing to the next.

Had I known how bad First edition, Second printing Pantone Plus was going to be, I never would have set it up as our most current standard. I would have simply told all my customers we are staying with First edition First Printing. Lesson learned.

 

[gordo]

I would not propose spec'ing Lab in this instance due to the above conversations regarding cross-instrumentation.

What I can hope for, is that some day Pantone implements their own internal Lab controls with a tolerancing of much less than the enormous variation that we see from one printing to the next.

Had I known how bad First edition, Second printing Pantone Plus was going to be, I never would have set it up as our most current standard. I would have simply told all my customers we are staying with First edition First Printing. Lesson learned.

It's not just the Pantone inks - it's also the paper they print on. I don't have the Pantone Plus swatchbook but I did check Goe vs the original and the Goe has a much higher level of OBAs which will impact the pastels (see attached blacklight view).

IMHO, you need to determine what the target for color is - your swatchbook, your client's a Lab value, a previously printed sample etc. Then proceed accordingly.

best, gordo

 

[slush11]

They're printed on on custom built waterless offset press located in their head offices in Carlstadt, NJ. The press uses split ink trains, or slots, so that they can print so many colors at once.

You can see a video of the process here: PTV

I hope this is received considering the date of the OP. BUt I can't watch that video. I've been trying and trying and it just keeps saying I need to update my Flash PLayer. I've updated it twice now. Is there another link somewhere?

 

[gordo]

Go here: https://www.youtube.com/watch?v=hkqMzLR8kS8