CHROMiX

Do I need training?

It’s a long story that I won’t go into other than to say we bought a package from an unnamed vendor that gave us press profiles and calculated the G7 curves we wanted for a coated and an uncoated stock AND was supposed to give us the ability to do more of this on our own as we needed to. Well, this didn’t happen. We do not have the ability to create profiles for additional stocks (or presses for that matter) and more importantly we cannot calculate additional curve data for different stocks.

That is the short version and it is still long. Anyway, we have come to the conclusion we need to purchase Curve2. What I would like to know from actual users how intuitive is this software? Will we require training on it or will we be guided. We are not color novices but I think you all know how complex a thing color management is. I have found some help on YouTube but am wondering about the documentation that comes with the software.

Any comments/incite is welcome.

Thanks in advance.

Rick

Would love to hear from anyone how VPR works and is it really worth it.

Hi Rick,

I’ll chime in here, and maybe that will get the ball rolling for other people to chime in. Or maybe everyone’s gone on vacation.

Hopefully the lack of Curve2 questions on this forum is an indication that the software is intuitive. I think the YouTube videos on Curve2 do a great job of showing you all the features of the software. We also have a 68-page pdf manual that comes with the software. And then we have our support staff that can answer any questions you may have. Many Curve2 users have upgraded from IDEALink Curve, and have already gained an understanding of how the interface works. We’ve added a lot of options and ways of viewing the data in Curve2, so I can imagine it might be a bit daunting at first glance. That said, the core function of the process is not really that complicated, and hasn’t changed a bit.

  • You set your press up to run properly under neutral curves
  • Make a run that includes a P2P target
  • Measure several sheets with a spectrophotometer
  • Bring the measurements into Curve2
  • Curve2 gives you control points that you put in your RIP
  • Optionally, you can make a second (or more) runs to verify accuracy, fine tune a difficult press or run a profiing target.

So I think the creation of the curves part of the whole process is pretty easy using Curve2. The harder part is setting up your press, making a quality profile afterwards, and dealing with unexpected problems that crop up.

Chromix has a network of G7 consultants around the county who could work with you, if you find you need that.

The pdf manual is around 10 MB, otherwise I would just pop it into an email to you.

VPR really does work. Whether it is worth it depends on how expensive a second run of the press is in your situation. It effectively eliminates the need for an additional run in order to create a profiling target that is curved. So if your press is expensive to run, it would be worth it. Considering the inherent variation in doing a second run, VPR can actually give you a more accurate final profile by calculating everything from the first run.

You mentioned 2 very different animals in your question.
First, the Curve 2 software is a good value depending on your number and type of presse0s in your facility/groups. The software is easy to use IF your presses are fairly new, stable, and in good working order. The software will bring the appearance of your printing into a similar pleasing look across products, presses, inks, paper and plates.
The second point you made was color profiles, depending on your quality requirements in proofing you probably will need an ICC color profile suite to reproduce the look of your printed products after the Curve software does it’s thing, depending again, on the number/type of presses your company has. The proofing suite and spectro hardware will be the expensive part but pays off on the long run to bring color management in-house and upgrade your knowledge base in the press and prepress areas about color management and create a dialog about color.
We paid a vendor $3800 for 4 color profiles that went right out the window as soon as the pressmen replaced the rollers in a magenta unit on press, instantaneously our profiles and proofs were rendered useless, of course this was done without telling anyone in prepress prior to doing the replacements. We were “enlightened” after the first job was put on and the press couldn’t match proofs AT ALL.
I’m currently employed at a cold-set newspaper and the Curve software works but the curve creation is more of a challenge due to the inherent variation in this type printing process, it can be done and the software will keep your manufacturing process more stable.
Easy to use IF your presses help you and not hurt you. The documentation I think some people might agree is a work in process. Version 1 was clunky but 2 is much improved.
Hope this helps,

Mark Thomas
Prepress Systems Lead

Tribune Publishing Company
Columbia Daily Tribune

Thanks for the answers. After I made the posts I discovered the YouTube videos and am finding them very helpful.

I don’t think setting up the presses will be too much of a problem. We just went through our G7 certification runs a few months ago and it is pretty much easy to remember. We haven’t changed pressmen or any of the other variables so we should be able to have a good press run or two.

As far a VPR goes… One opinion I got is that it is really for color consultants who do this a lot. In fact I was told that if I got sheets that weren’t quite close enough, VPR would virtually apply an edit to get closer. That isn’t how I see it described on line. There I understand that it is just to avoid a second, confirmation run, saving that time and money. Are they both correct? Kind of different animals.

We are not sure going into this how many more sets of curves we might want. If one more takes care of things then no, I don’t think VPR is worth it. But you never know. We thought the one set of coated curves would reasonably take care of all coated stocks.

One other question. I have been reading the G7 “How To” and finding it very helpful. I think I am on my sixth time through already. Section 4.7 they talk about correcting gray balance. I find this confusing a little. In that first section they say it is needed only if the maximum difference between C,M and Y in any Output Curve Set row is equal to or greater than 1%, it is recommended. Am I not getting this? at 4.6 there is figure 4.2 with a sample set of curves. The difference in more than 1% a lot of the time; is this an example of when to do this? Or am I just not understanding what they are saying?

Later, at 4.7.2, it says not to correct gray balance if “The device will be gray-balanced on the next print run by physical adjustments such as modified cmy colorant levels.” Are they talking about NPDCs? Or something else?

Sorry if I am being thick. I am just trying to get everything together in my head before we begin. When the consultant was on site, I, of course, got called away often for business things and missed some of what was happening at key moments.

Thanks for all your help. I am actually looking forward to going through this process and using Curve2.

Rick

It’s been over a week and no one has responded to my last question. I will try again (I know, everyone is at least as busy as I am but I really could use and answer to this one:

One other question. I have been reading the G7 “How To” and finding it very helpful. I think I am on my sixth time through already. Section 4.7 they talk about correcting gray balance. I find this confusing a little. In that first section they say it is needed only if the maximum difference between C,M and Y in any Output Curve Set row is equal to or greater than 1%, it is recommended. Am I not getting this? at 4.6 there is figure 4.2 with a sample set of curves. The difference in more than 1% a lot of the time; is this an example of when to do this? Or am I just not understanding what they are saying?

Later, at 4.7.2, it says not to correct gray balance if “The device will be gray-balanced on the next print run by physical adjustments such as modified cmy colorant levels.” Are they talking about NPDCs? Or something else?

Sorry if I am being thick. I am just trying to get everything together in my head before we begin. When the consultant was on site, I, of course, got called away often for business things and missed some of what was happening at key moments.

Rick

Hello Rick,

Thats unfortunate you had to miss time with your visiting consultant.

4.7
It is possible that your press conditions will natively meet the verification requirement of +/-1% when using linear or raw CTP plates but unlikely. Typically the calibration run will require steeper curve adjustments than +/- 1%. Hopefully you will get to +/-1 on your verification run by carefully adjusting your solids while minding gray balance without breaching 5dE for KCMY.

4.7.2
When analyzing the P2Ps from a run and you are close but not close enough, say +/- 2~3% then the idea is that you could probably adjust SIDs on subsequent pressruns to meet G7 aimpoints for gray balance and npdc.

Gray balance and NPDC are independent criteria but controlled on press by the same thing solid ink density. If/when you adjust SIDs on press chasing gray then you also have to be careful to move the right inks to avoid lightening or darkening NPDC at the same time. For example if the gray balance is too blue, then you can safely add yellow without affecting NPDC but if you reduce cyan and magenta instead then your NPDC will lighten.

Thanks,
Matt Louis

On 8/30/11 10:24 AM, “rstubbie7” <rick@odell-printing.com> wrote:

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