Standard Finishing
4Over

Announcement

Collapse
No announcement yet.

GRACoL Dot Gain Worksheet

Collapse
CanonKonica Minolta
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • GRACoL Dot Gain Worksheet

    Does anyone have the GRACoL Dot Gain Worksheet? Thanks

  • #2
    Re: GRACoL Dot Gain Worksheet

    Are you referring to the G7 Graph Paper for plotting NPDC curves? Available at www.gracol.org

    Comment


    • #3
      Re: GRACoL Dot Gain Worksheet

      Yes I want to plot the dot gain for each color. I went to www.gracol.org but I could not find the work sheet. Do you have it? Alan

      Comment


      • #4
        Re: GRACoL Dot Gain Worksheet

        You're probably talking about the worksheet I created. It's not official. The official stance focuses on NPDC, not dot gan/TVI. Where did you hear about the worksheet? Have I sent it to you before?

        Don

        Comment


        • #5
          Re: GRACoL Dot Gain Worksheet

          BTW, I would recommend you using IDEAlink Curve software (official software, which uses a spectrophotometer), or PerfX Press Curves (which uses densitometer, as an alternative)

          http://www.gracol.org/IDEAlink/
          http://www.tglc.com/english/PerfX/Press%20Curves.html

          Neither are free, but I have not made by calculator to compete with these products. I made it for me, since I was interested in what was going on behind the scenes of the G7 How-To (since the formulas are in there, which lead to me looking for other formulas to get info I needed, filling in the gaps, and it took a lot of work for me to do, just for curiosity, and it got me matching GRACoL2006_Coated1v2 proofs without having to do a press run, by using the calculator with my existing press profile and existing plate curves, getting Lab values, plugging them in, and finding what changes I needed to make to my existing plate curves, which is what I was after). However, I have given it to some people to see what they thought, hoping to get feedback. I haven't gotten much feedback, but what I have gotten has been that the NPDC portion of my calculator is better than the TVI portion, which leads me to say for everyone just to use IDEAlink Curve. I make no claims that my calculator is correct. I was told by Loius Dery of PerfX on pab list that it is within 1% correct, which was close enough for me until by boss decides to do anything. Since he's not in a hurry to move to GRACoL2006_Coated1v2, most of my testing has resulted in just me wasting my time.

          Don

          Comment


          • #6
            Re: GRACoL Dot Gain Worksheet

            Hmm

            I think he was referring to the Fan Graph paper ?

            I would agree that the Curve tool is a way better idea considering the time it would take to measure and plot it out.
            Not to mention the potential for mistakes A very expensive press WAITING for you to make the curves.....Id spend the $600

            John

            Comment


            • #7
              Re: GRACoL Dot Gain Worksheet

              Alan wasn't referring to either the fan graph paper or to Don's Excel sheet, but simply to a sheet for manually recording your dot gain for comparison to a given target dotgain (we talked off list). Suffice to say, official dot gain values for Gracol don't exist.

              Comment


              • #8
                Re: GRACoL Dot Gain Worksheet

                I have to say that I must take back what I said before. When I said that making the Excel worksheet had been a waste of time, nothing could be further from the truth. I have used Excel in creating my new business, and it will be required for half of the running of my business (money and risk management to start with, which is essential in what I'm doing), so me learning Excel better has been a great thing in the long run.

                Don

                Comment


                • #9
                  Re: GRACoL Dot Gain Worksheet

                  Don, new business?
                  Sounds interesting.
                  Are you already able to give more details on the type of business you seem to plan?
                  Regards, Henk

                  Comment


                  • #10
                    Re: GRACoL Dot Gain Worksheet

                    Sure they do.... well "target dot gains" at least..
                    See attached PDF.
                    Vee

                    Comment


                    • #11
                      Re: GRACoL Dot Gain Worksheet

                      Hi Vee,

                      What you've posted is per the old specification. The current 2007 Gracol specification omits references to SID and TVI as anything but historical references...can be downloaded here: http://www.gracol.org/specification/...2007errata.pdf

                      Comment


                      • #12
                        Re: GRACoL Dot Gain Worksheet

                        Hello Michael,

                        My apologies, as you are correct in regard to the 07 spec. I didn't catch any specific reference to the new or old, and the "old" Gracol does have dot gain specs. I guess I read too much into your statement, "official dot gain values for Gracol don't exist."
                        FWIW - I recently set up a CtP & 4c press based on the "old" data with stellar results. And the GB was very pleasing.

                        Regards,
                        Vee


                        edit 4 spelling

                        Edited by: Vee on Feb 18, 2008 10:19 PM

                        Comment


                        • #13
                          Re: GRACoL Dot Gain Worksheet

                          Henk,

                          I'm not ready to give that information out publicly, and may never give it out on these forums.

                          Don

                          Comment


                          • #14
                            Re: GRACoL Dot Gain Worksheet

                            Confusion for me is what I say. How many GRACoL TVI & Density standards are there out there? I have a Bridges Poster telling me TVI for GRACoL 2006 C1V2.icc is (KCMY) 20/17/17/16 and densities of 1.7/1.45/1.45/1.0 respectfully. These are different than what you guys are posting. Is this a true standard when it is coming up slightly different. Is there a charted history of the changes to the GRACoL standard.

                            Jardo

                            Comment


                            • #15
                              Re: GRACoL Dot Gain Worksheet

                              Yeah, it is confusing. The Bridges chart is kind of blurring the line...melding ISO 12647, G7, legacy Gracol, and some other metrics together in one chart. Its not Officially Gracol...at this time, but it is referenced in the new G7 Pressman's guide. Suffice to say that there's some disagreement on what's beneficial and necessary to include in a reference chart. It does state on the chart that the density numbers are only suggested starting numbers and that Lab values take precedent. I'm not a big fan of the Bridges chart...It obviouslytappeals to those who would opt for density and TVI metrics, but solid Lab and a fully defined NPDC is les ambiguous. Plus, if you got your chart handy, read the fine print directly under the chart regarding gray balance CMYK values.

                              In any event, I suppose I shouldn't be so abrupt to say that "official Gracol Den/TVI metrics" don't exist, because that might change depending on who gets their way within the Gracol Committee.

                              Comment

                              Unconfigured Static HTML Module

                              Collapse

                              Static HTML Module Content
                              4OverStandard FinishingDuploSmartsoft (Presswise)CanonKBAUltimateTharstern
                              4OverStandard FinishingDuploCanonKBAKBA4 PeesSmartsoft (Presswise)TharsternUltimate

                              What's Going On

                              Collapse

                              There are currently 4557 users online. 115 members and 4442 guests.

                              Most users ever online was 6,597 at 10:25 AM on 04-20-2018.

                              Working...
                              X