GRACoL 7 - spectro with UV at end of name

[disbellj]

That's a good idea Rich, but would solids be much off using UV-filtered spectro vs non-UV-filtered (since this is the first step before NPDC)? If the L* values are similar using UV-filtered vs not along the whole scale, I can plug the L values from the target into an NPDC calculator I made, and it will convert the L* to density values, I minus paper, and plot the NPDC. This still doesn't say that the actual Lab values of the colors are going to be close though, right? That is where my main concern is: If I want to match a color on a printed piece a customer brings in and ask me to match, if I want to use the standard profile for converting captured Lab values to CMYK values, then this is where I see the problems coming in. Not at press NPDC so much, but converting Lab captured using UV-filtration, and converting it to CMYK profile that doesn't use UV filtration. Will it look the same when printed as if I had captured that color from the printed piece not using UV filtration and converting to official profile that doesn't use it. And my concern lies in mainly the light colors area (pastels aka colors with equal to or less than say 20% of any process color).

Regards,

Don

You can also use a densitometer to set the gray balance. Include one of Don Hutcheson's old Gray Finder targets on the test form. Measure the patches with with all filters on. Neutral is the patch at which the filters all read equal. The target tells you the adjustment to make.

[glenncolorguy]

For some reason, proofing manufacturers almost always supply UV cut devices withe their systems (probably because from a scientist's point of view it seemed like a "clean" approach at the time).

Unfortunately, such readings often don't correspond to what we actually see. A sheet with optical brighteners will look blue to us but may measure as neutral when using a UV cut instrument.

Taking a quick at the larger question, it is simply not correct for a grayscale printed on a bluish paper to be uniformly neutral. The paper is part of the image, and a perfectly neutral grayscale is not something to be desired when printing onto a strongly bluish paper.

IDEAlink curve tool does a good job scaling NPDC to paper white. Unfortunately, GRACoL verification, tied to a fictional and fixed 0a* -2b* whitepoint has tended to lag in this respect, often causing perfectly good G7 sheets produced on bluish papers to get false fails.

[meddington]

Good points Glenn...

Taking a quick at the larger question, it is simply not correct for a grayscale printed on a bluish paper to be uniformly neutral. The paper is part of the image, and a perfectly neutral grayscale is not something to be desired when printing onto a strongly bluish paper.

Yes. From the point of view of the proof though, the problem arises in the simulation of the GracolCoated1 white point on a paper with optical brighteners. As it is, there isn't fool proof method for ensuring an accurate white point for a given paper with OB content, given instrument and viewing conditions. best results in these situation can be subjective. Of course if one's press stock deviates from 0a*, -2b*, one would have to consider what's more important...matching the charaterization data white point, or the white point of the actual print stock.

Unfortunately, GRACoL verification, tied to a fictional and fixed 0a* -2b* whitepoint has tended to lag in this respect, often causing perfectly good G7 sheets produced on bluish papers to get false fails.

True. Additionally, there has been some discussion in the Gracol committee of "paper relative" scaling when evaluating press sheets.

[disbellj]

Maybe I should tell my boss to wait another couple years.

[glenncolorguy]

Good points Glenn...



Yes. From the point of view of the proof though, the problem arises in the simulation of the GracolCoated1 white point on a paper with optical brighteners. As it is, there isn't fool proof method for ensuring an accurate white point for a given paper with OB content, given instrument and viewing conditions. best results in these situation can be subjective. Of course if one's press stock deviates from 0a*, -2b*, one would have to consider what's more important...matching the charaterization data white point, or the white point of the actual print stock.

True. Additionally, there has been some discussion in the Gracol committee of "paper relative" scaling when evaluating press sheets.

Mike,

It is true that simulating GRACoL C1 with an OB paper is tricky. OB's confuse the process in unpredictable ways.

But most "real" #1 sheets contain OB's and strong -b* values. Matching characterization data white point is important to color experts, but matching the white point of the actual job stock is important to clients, so I'd go with the people who are paying the bills...the clients.

Hopefully, adoption of paper relative scaling will reduce this conflict and make it possible to satisfy both needs

[disbellj]

OK guys, an update:

Kodak came in, and the Eye-One Pro does have UV cut.
The Kodak MatchPrint Proofing Solution (proofing on SM240P proofing paper) I believe was told to me to be UV cut required. I believe today that I was told that this may not be the case and maybe I can use no UV filter with the software (would be nice, especially if what I find gets the boss to maybe request proofing and press papers more in line with the standard white point so UV filtration was not needed in proofing, so that same type of intrument can be used in all places in workflow).

Today I found they also delivered an XRite spectrodensitometer 500 series that I was told does not have UV filter on by default. So it looks like I can use this to scan Lab values from a printed piece or proof for reproduction, and to also verify my proofs (although not meant to per the software expert, but I'll have to confirm tomorrow), since the XRite 500 series is meant to be used at press.

So we are going to set up to GRACoL 7 for coated paper (and also FOGRA 29 for uncoated paper since there is no ICC profile for paper type #4 using G7, and FORGRA 29 looks pretty close) using a spectro that does not have a UV filter. Since I haven't been told someone is coming in to do it, I will probably be the one to do it, and have no qualms about it as long as I have the non-UV-cut spectro and I think white backing, and of course my calculators (although I'd love to see the difference between my results and IDEAlink Curve 2, but that may or may not happen).

Thank you ALL for your replies.

I will probably keep everyone updated in this thread with possibly Excel calculators I made and information I may learn as I go - that although pertains to my situation, may also help someone else who reads this.

Regards,

Don

[disbellj]

Disregard what I said before about the 500 series that's supposed to be used at press. It's just a densitometer.

Now that we have a Certified proof (which I can't validate as being within tolerances myself, since I only have two UVcut spectros and no UV included spectros, so my calculator does no good when comparing apples and oranges), my boss decided he wanted to make some plates and put on press to see what we get. This is as bad as Kodak saying to basically do the same thing, send them a press sheet of our current condition and they'd make a press profile for us to use in proofing.

(Note: We just set proofing up to match GRACoL2006 / GRACoL 7 using the included certified GRACoL profile in our proofing solution, so we don't need to have a custom ICC profile made, although we most likely paid for it already, and having a GRACoL 7 proof is not going to magically make the press print to GRACoL 7).

Why is it I feel like I'm in bizzaro world?

(monumental rant following)

It's like running full speed ahead into a brick wall trying to get anybody to see what I'm talking about. It would have been much easier for me to have stayed ignorant and let them stay ignorant too. My boss just wants to get it over and have it done with, and doesn't care about the details. He'd rather just not know them and let someone take care of it. No wonder he gets sold crap by "experts" who really don't seem to EVER do all that needs to be done. They take care of press but don't think/care about prepress, or vice versa.

Same old story. Nobody seems to take everything into account - prepress AND press. These are supposed to work together.

And frankly, I've become more apathetic since I used to post here, so I really easily get to the point I don't care anymore. I just get easily pissed off and wonder why I give a crap at all anymore. I try to save the boss about $3,300 on hard drive and RAM upgrades for a new Mac Pro 8-core, and the boss gets mad because I didn't tell him everything I needed while he was standing in the Apple store. I got a new Mac so I should be happy right? Well, I took a couple weeks building it up, and it's not backed up, so no I'm not happy about the fact that it could crash and all that time would be wasted that I spent, and I would have to start over again. All because I didn't ask for the HD when I ordered the damn machine. I never intended to buy the HD and RAM upgrades from Apple. I wasn't expecting a thank you, but I hardly expected for him to get mad. So I was in a funk through new years (yeah this happened on New Years Eve). And now everything I had asked for or talked about gets delivered and I'm supposed to make it work, although not one damn thing is as I asked for.

Actually, that's not true. I do have my image centered in the proofing paper (so I got one thing I asked for and actually insisted on), and it took 3 days for the proofer installer tech to do that. And to think: I should have been getting actual training at that time, but the time was wasted trying to get an image to center in a piece of paper. 3 days. Why? Because we are doing imposition proofs on a 7880 instead of me getting the wider printer that I asked for which would have made this easy. So we live with what we got, and they had to make it work.

Again, why is it I feel like I'm in bizzaro world? And why do I give a crap at all?

(end of rant - for now)

Don

[stargate]

If you can quit and save yourself lots of stress. Stress kills, just like cancer.

[glenncolorguy]

It's like running full speed ahead into a brick wall trying to get anybody to see what I'm talking about. It would have been much easier for me to have stayed ignorant and let them stay ignorant too. My boss just wants to get it over and have it done with, and doesn't care about the details. He'd rather just not know them and let someone take care of it. No wonder he gets sold crap by "experts" who really don't seem to EVER do all that needs to be done. They take care of press but don't think/care about prepress, or vice versa.

Same old story. Nobody seems to take everything into account - prepress AND press. These are supposed to work together.

Don

This is really the central problem, much more than UV vs Non UV, and certainly deserves its own thread.

The print industry has drifted over the years into permanent crisis management mode, ignoring the larger view and never thinking in terms of systems, only in individual fires that need to be stomped out quickly.

[disbellj]

Well, I'm not to the point yet that I can quit, but this is why I started researching trading Forex a couple years ago. I look forward to a day when I will be my own boss on my own schedule. Not complaining really. I have it better than most. Unless something like this happens (new equipment, etc., which is almost never), then I do what I do and get left alone, which is how I like it.

Until then, I have determined to try and get the company I work for into a place that they will be in good shape when I leave. It's just I'm not that good at communication and/or they aren't. I couldn't do their job, but I do know mine pretty well. I'd say more than the average prepress person for sure. But that's because I've been doing it for almost 15 years now.

I can't expect them to understand me I guess. That's why I lay blame at the vendors, because they should recommend the full solution. They knew we were moving to GRACoL. They knew we wanted to replace our wide Sherpa 2 proofer. They gave us the wrong printer, and then recommend we make a profile of our press in the current condition, gave no instructions on GRACoL for press, and also give us a spectrodensitometer I thought, but it doesn't have Lab values from what I can see, only a main menu that has density and dot gain, so it's just a densitometer.

If I was ignorant of something, I would hire experts too. If I am ignorant of something, I mainly ask the experts here. I don't mind not knowing something and being ignorant of it. We're all ignorant of something (more than one thing, because none of us know everything, and who would want to anyways). But if I'm wrong, I want to learn what is right. But not everyone is like that. They just would rather pay for someone to make it right.

But when the experts are not doing the right thing, what is the avenue for someone that doesn't even know it? Without me being their pain in the ass, the company I work for wouldn't know they weren't given what they need. They would make the order, the people would come in and deliver something, install it, and I'd have to work with what they installed, whether it is what was ordered or not, or needed or not. Because normally I wouldn't know what was ordered. I wouldn't know it until one day it was delivered and installed.

And all I can do is either shut up or say the problems I see compared to what I asked for. This is the first time I have been asked my opinion. Before this, the vendor would just make a recommendation, and that is what would be done. This time, I was asked, made my recommendations, and still got what the vendor decided to give, and I'm so pissed off I have to say something to the boss and ask why they even fool with the ignorant vendors anyways and not go straight to X-Rite like I recommended, and let the chips fall where they may. I'm to the point of telling him to get me an Eye One without a UV filter, and I'll use the free GMG software at press to see if I can get them set up to GRACoL at press since nobody else (it seems) has bothered to look into doing this.

Regards,

Don

If you can quit and save yourself lots of stress. Stress kills, just like cancer.