GMG vs EPSON 9900 - Spot Color Tolerances

[Kido]

Hello

The EPSON 9900 is praised for its extended gamut, which should lead to improvements when reproducing spot colors.

I have been told that…
95% of the spot colors could be printed within a tolerance of ∆E 2
98% of the spot colors could be printed within a tolerance of ∆E 5


Could anyone confirm these percentages?
And what are the target values that GMG used for ∆E calculation?

I have been searching for some sources, but without succes.


Thanks in advance

 

[venkatnagu]

hello Mr. kido

This is venkat i know gmg lab target values, if iam free tommorow i will tell u...

 

[chevalier]

I'm using CGS-ORIS and not GMG to drive an Epson 9900 (also using CGS-ORIS paper). I'm able to hit all but ~3% of the Pantone+ coated book within 3dE 2000.

 

[TerryWyse]

And what are the target values that GMG used for ∆E calculation?

GMG would be using the "official" L*a*b* values from Pantone as their target for comparison.

I can't confirm or deny their numbers. The gamut of the 9900 is what it is (depending on media of course) so I don't believe you're going to see huge differences, assuming these claims are true, between the different RIP vendors.

Terry

 

[Kido]

Thanks for the help so far.
@ Venkat: how will you provide me the values? And what's your source for the values? ISO standard or something?

Maybe we have to wait for Pantone Live for real Lab based spot color matching…

 

[venkatnagu]

hi,

CGS-ORIS paper may not be give a accurate result, iam sure technova paper gives a better result(B'coz we are using technova & novatech paper).

All the Best

 

[venkatnagu]

We are using lab values according to the ISO - 12647

 

[sasa311027]

I have been told that…
95% of the spot colors could be printed within a tolerance of ∆E 2
98% of the spot colors could be printed within a tolerance of ∆E 5


Could anyone confirm these percentages?

White points - 3640 "Lab values" from Pantone's patches measuring.
Paper - EPSON S042003, Printer Epson 9900. RGB-output profile, without any RIPs, driver only.
I think it can help you.

 

[Kido]

We are using lab values according to the ISO - 12647

Does ISO12647 describes tolerances for spot colors?
I thought it was a guide for CMYK.

What are the tolerances then?


Thx!

 

[Johu]

hi,

CGS-ORIS paper may not be give a accurate result, iam sure technova paper gives a better result(B'coz we are using technova & novatech paper).

All the Best

Do you have some sort of proof about this. I mean it is pretty odd to throw such an allegation up in the air that CGS paper may not give give accurate result, just because you use technova paper???

 

[rich apollo]

Maybe we have to wait for Pantone Live for real Lab based spot color matching…

Why? You can check the results yourself. Print a swatch book and measure the results. Have the vendor print it and send you the sheets to check. If you need a swatch book document, I have one I'm glad to share.

 

[Johu]

Why? You can check the results yourself. Print a swatch book and measure the results. Have the vendor print it and send you the sheets to check. If you need a swatch book document, I have one I'm glad to share.

Been there, done that. There's just one problem with that. just use your spectrophotometer to measure your pantone swatch and compare the measured value against the pantone library values. I would be very surprised if they come even close. What I do in very demanding cases is that I always measure either a printed sample or the swatch book for "real" reference as I find the library values some what misleading. I have not checked the pantone+ library, but I have cross checked earlier versions against their swatch counter parts.

 

[rich apollo]

Been there, done that. There's just one problem with that. just use your spectrophotometer to measure your pantone swatch and compare the measured value against the pantone library values. I would be very surprised if they come even close. What I do in very demanding cases is that I always measure either a printed sample or the swatch book for "real" reference as I find the library values some what misleading. I have not checked the pantone+ library, but I have cross checked earlier versions against their swatch counter parts.

Is your complaint with the library values, the swatch books, the spectro, or the clients' expectations? The library consists of the defined target values. The swatch books are attempts at reproducing those targets within the capabilities of the manufacturing process. My guess is that the flaw is in the swatch books.

Your complaint sounds like blaming the guy who designed your car for the fact that you have a flat tire. Do you feel that the library values are unreasonable?

 

[Johu]

Is your complaint with the library values, the swatch books, the spectro, or the clients' expectations? The library consists of the defined target values. The swatch books are attempts at reproducing those targets within the capabilities of the manufacturing process. My guess is that the flaw is in the swatch books.

Your complaint sounds like blaming the guy who designed your car for the fact that you have a flat tire. Do you feel that the library values are unreasonable?

Sure it's the swatches (duh!), but for the price that you have to pay for the swatches I do expect them to be little closer to the library values. So yeah I am blaming the guy who designed my car because he quite obviously did very lousy job as his manufacturing dept. can not manufacture what he designed.

And to be quite honest I tend to think the result here being the printed job should reflect the design ie. The library values. What good are the library values for if even their own representation of them is not accurate.

Are you gonna use a flat tire comparison when your customer has signed off a contract proof which has pantones reproduced according to library and your printing dept can not reproduce them and even the swatch shows that they are different? Because I know I can't. This is why with important colors I measure the actual print or atleast the swatch.

 

[rich apollo]

Sure it's the swatches (duh!), but for the price that you have to pay for the swatches I do expect them to be little closer to the library values. So yeah I am blaming the guy who designed my car because he quite obviously did very lousy job as his manufacturing dept. can not manufacture what he designed.

Well, I'd blame the gang in manufacturing, but at least you and I are in the same chapter, if not on the same page.

Are you gonna use a flat tire comparison when your customer has signed off a contract proof which has pantones reproduced according to library and your printing dept can not reproduce them and even the swatch shows that they are different?

Of course I am! I'll use that story, scantily clad women(or men), liquor, whatever it takes...

Because I know I can't. This is why with important colors I measure the actual print or atleast the swatch.

If you have the chance to measure what the client was looking at before you get to press, then that's definitely the way to go. Just for giggles check a couple of swatch books against one another. And, what about next year? When you get new swatch books do you expect to have to measure all over again? Each new swatch book is gonna' be a bit different.

Is each substrate that you print on going to produce similar enough results to satisfy you and your client?

 

[Johu]

Well, I'd blame the gang in manufacturing, but at least you and I are in the same chapter, if not on the same page.

I think we are on the same page here

If you have the chance to measure what the client was looking at before you get to press, then that's definitely the way to go. Just for giggles check a couple of swatch books against one another. And, what about next year? When you get new swatch books do you expect to have to measure all over again? Each new swatch book is gonna' be a bit different.

Is each substrate that you print on going to produce similar enough results to satisfy you and your client?

I do agree that the swatches do also vary a bit, but still the differences between printed samples (as long as the substrate is similar or even close) are closer to one another than printed vs library values. And again going back to the fact that software operate on the library values and designers usually pick the colors from the swatches and that's where this thing goes slightly crooked. I hope that you agree atleast partly that pantone is making a lot of money for the swatches and yet they do not accurately represent their library values.

A lot of the cases where me or my customers need to be very careful with the pantone colors involve brand colors (not a big surprise) and most of those times there are printed samples of earlier jobs available to measure.

 

[drummerpaco]

Well, I think Pantone should control the swatch book, and colour chip set more carefully and tightly.
I have experienced ordering swatch book and chip set having ∆E over 5-6.Over three months ago, I compared upgraded pantone library (from Pantone website) vs Swatch book (swatches and chip set) that I purchased over 6 months ago. some are individually ordered as well, so newer and some comes very close and some have over the roof deviation (∆E 8-10).

I personally liked when they updated library because all application share same L*a*b* value and control the color by L*a*b* value, however, there is no way to get Pantone L*a*b* value from Pantone except your are ink vendor. Also the Pantone claims that Pantone swatches and chipset is reference guide, not colour target.

I do not trust wording "Reference guide" because in reality, Pantone numbers does not mean anything if ink vendor, pre-press and customer cannot share same L*a*b* value. People might say we have do the proofs and ink drawdown because of these reasons, but in printer and production manager perspective, it cost the time and money. In reality, fast faced environment cannot afford too much time spending when it comes to approval after approvals.

For me, I ask the physical color target even though customer have same pantone swatches because I want to measure the Lab value on them and control the color by quantitative values.

Do you guys have better way of controlling Pantone colors?

 

[D.M.]

Some time ago I compared samples from GMG and E4900 with printed Pantone swatches (6 months old). Few examples below.

 

[drummerpaco]

comparison

comparison

Well, I believe GMG and other RIP software has its own Pantone Plus L*a*b* value, however these colors are modifiable since you can change the L*a*b* value.

But again, what is the target of the Pantone Plus is the question not which reference is more accurate since everyone has its own pantone reference and yet they are all different since the tolerance is varies

 

[Johu]

Well, I believe GMG and other RIP software has its own Pantone Plus L*a*b* value, however these colors are modifiable since you can change the L*a*b* value.

But again, what is the target of the Pantone Plus is the question not which reference is more accurate since everyone has its own pantone reference and yet they are all different since the tolerance is varies

Atleast CGS Color Tuner has Pantone licensed Libraries which are then optimized for respective printers during calibration. So they are not their own values.

But again to my experience the Pantone library values do not represent printed values accurately. In very precise cases it s always better to measure printed samples and let the rip figure best possible printer match for that color.