Does the GRACoL profile have the dot gain baked in?

[HarveyDunn]

I'm designing a color-critical piece that will be printed on a sheet-fed press using the GRACoL profile.

I'm a bit confused by dot gain. I'm using the usual Adobe products to produce the piece: InDesign, Photoshop, Illustrator. Do I need to do something to account for dot gain? Or is this already "baked in" to the ICC Profile?

Also, we are going to do a first round of proofs with a service bureau, because we haven't chosen the printing company for the project yet, but the client wants to see a realistic simulation of the final outcome ASAP. Do I need to do something re dot gain before sending the service bureau the files for making the proofs? I don't want to create any unrealistic expectations - i.e. it looked great in the independently-produced proof but then the printing company says they can't actually match it.

 

[gordo]

I'm designing a color-critical piece that will be printed on a sheet-fed press using the GRACoL profile.

I'm a bit confused by dot gain. I'm using the usual Adobe products to produce the piece: InDesign, Photoshop, Illustrator. Do I need to do something to account for dot gain? Or is this already "baked in" to the ICC Profile?

Also, we are going to do a first round of proofs with a service bureau, because we haven't chosen the printing company for the project yet, but the client wants to see a realistic simulation of the final outcome ASAP. Do I need to do something re dot gain before sending the service bureau the files for making the proofs? I don't want to create any unrealistic expectations - i.e. it looked great in the independently-produced proof but then the printing company says they can't actually match it.

You don't have to do anything about dot gain it's built into the ICC profile. Actually the tone reproduction curve is built in.

What you have to do is determine if the printers (and service bureaus) that you're considering actually align their process to the specification/standard that you are using. If they aren't then it doesn't matter that you're using a standard in creating your artwork - the color chain would be broken.
If you use a service bureau and not the printshop for your color proofs then you also need to know that the service bureau's proofs actually represent what the final printshop will print. Frankly, IMHO, you may be setting yourself up to be caught between suppliers if you are not satisfied with the final result. If I were you I would first determine which printshop will get the business and then work with them to get proofs and/or have them identify which service bureau makes proofs that they accept as reflecting what their presswork will look like.

gordo

 

[HarveyDunn]

What you have to do is determine if the printers (and service bureaus) that you're considering actually align their process to the specification/standard that you are using. If they aren't then it doesn't matter that you're using a standard in creating your artwork - the color chain would be broken.

Any ideas as to how to do this? I mean obviously I can ask them if they use the GRACoL profile, but beyond that (and accepting their "yes" at face value) what else can I do?

If I were you I would first determine which printshop will get the business and then work with them to get proofs and/or have them identify which service bureau makes proofs that they accept as reflecting what their presswork will look like.

Good advice, I'm sure, but the client wants to see a proof ASAP, so it is out of my hands.

 

[gordo]

Any ideas as to how to do this? I mean obviously I can ask them if they use the GRACoL profile, but beyond that (and accepting their "yes" at face value) what else can I do?

You need to ask the printer/service bureau what print standard/ specification that they've aligned their production to. If they give you a blank stare then you're in trouble. They need to have aligned to ISO 12647-1 or GRACoL 7.

Good advice, I'm sure, but the client wants to see a proof ASAP, so it is out of my hands.

Out of your hands? Who's in charge of production - you or your customer?

I would tell my customer that one cannot have accurate proofs until the printshop that's doing the job has been selected. Any proofs before that point will be fair representations - but can't be considered as contract quality since they're not being made by the actual printshop that's doing the job.

Gordo

 

[HarveyDunn]

GRACoL 7 - is that the same as G7? Is it enough to know that a printer is G7 certified, or do you have to do something else to make sure they are still operating that way even after the inspectors or whoever left the plant?

The client is going to be billed directly by the printshop, so I'm not going to be able to get any proofs the chosen printshop until (1) it has been chosen and (2) until the client has opened an account with them. That is still a long way down the road. So, yes, I know it is an imperfect solution, but I've got to go to service a bureau to get a set of proofs made in the meantime. I do know that I cannot hold them out as "contract" proofs. Just trying to make the best of an imperfect situation by asking if there is anything I can do to make sure the service bureau output is a realistic facsimile of the output of a press running the GRACoL profile (other than, obviously, making sure the service bureau understands I want a GRACoL proof!)

 

[gordo]

GRACoL 7 - is that the same as G7? Is it enough to know that a printer is G7 certified, or do you have to do something else to make sure they are still operating that way even after the inspectors or whoever left the plant?

GRACoL 7 is the GRACoL Publication. It contains color reproduction specifications for sheetfed offset lithography utilizing the existing ISO 12647 - 1 defined inks and paper.

G7 is both a definition of grayscale appearance, and is one of several calibration methods for adjusting any CMYK imaging device to simulate the G7 grayscale definition. It is not a specification for color reproduction. So, two shops can be G7'd and deliver different color.

The folks that you deal with may have all this mixed up (an unfortunate characteristic of this industry) so it's best to ask for clarification whenever the terms are being used. Don't assume. Don't be afraid to ask questions.

The client is going to be billed directly by the printshop, so I'm not going to be able to get any proofs the chosen printshop until (1) it has been chosen and (2) until the client has opened an account with them. That is still a long way down the road. So, yes, I know it is an imperfect solution, but I've got to go to service a bureau to get a set of proofs made in the meantime. I do know that I cannot hold them out as "contract" proofs. Just trying to make the best of an imperfect situation by asking if there is anything I can do to make sure the service bureau output is a realistic facsimile of the output of a press running the GRACoL profile (other than, obviously, making sure the service bureau understands I want a GRACoL proof!)

The key is to make sure that expectations are set communicated clearly and correctly. Ask the service bureau about which printshops they've supplied proofs to and then talk to those print shops and ask about their experience aligning presswork to those proofs.

gordo

 

[Stephen Marsh]

@HarveyDunn, I agree with Gordo.

This should be driven by the final printer, or the final printer should be willing to accept the proofs produced by another party.

That being said, many proofing systems have a "certification" add-on, where a colour bar is printed and measured by a spectrophotometer. The measurements are compared to the specification that is being proofed and a report label is generated showing the measured dE values and the target dE tolerance values. This provides more confidence in the proof, however it does not mean that an unknown printer will accept the unknown proof - even if it does have a certification label. On a proofer with an inline spectro, the label is often printed by the same proofer that produced the print, directly on the proof. With a proofer that has an offline spectro, a Dymo label printer is often used to print the label and the proof label is then attached to the (hopefully) corresponding proof.

Some samples of proof verification stickers can be found here:

http://printplanet.com/forums/prepress-workflow-discussion/30521-certification-stickers


Stephen Marsh

 

[HarveyDunn]

You know what? I regret my use of the word "proof". What I should have said is: I'm going to get a printout from a service bureau because I need a more accurate printout than what I can achieve with my in-house laser printer.

 

[rich apollo]

HarveyDunn, if you had a RIP and an inkjet device you could create your own GRACoL compliant proof right there in your office/spare room/garage.

You don't need to worry about dot gain.

 

[TerryWyse]

If you're committed to using GRACoL as your specification/standard/profile, then the first place to go would be the IDEAlliance website and find a "G7 Master Printer" that's qualified for GRACoL (note: not all G7 Master Printers will necessarily be GRACoL-qualified...it could be SWOP or simply qualified for G7 gray balance).

Terry

 

[TerryWyse]

GRACoL 7 - is that the same as G7?

NO! GRACoL (and it's not "GRACoL 7" as far as I know) is a colorimetric aimpoint that has G7 gray balance/tone characteristics......G7 is a gray balance/tone methodology but NOT an explicate colorimetric target.....unfortunately, people get these mixed up all the time.

Is it enough to know that a printer is G7 certified, or do you have to do something else to make sure they are still operating that way even after the inspectors or whoever left the plant?

They need to be not only G7 *qualified* but you need to know what colorimetry they're targeting....GRACoL, SWOP3/5, SNAP, etc. If it's commercial sheetfed printing, it's likely going to be GRACoL.....web offset publication, it will likely be one of the SWOP variants. These are all under the G7 umbrella.

The client is going to be billed directly by the printshop, so I'm not going to be able to get any proofs the chosen printshop until (1) it has been chosen and (2) until the client has opened an account with them. That is still a long way down the road. So, yes, I know it is an imperfect solution, but I've got to go to service a bureau to get a set of proofs made in the meantime. I do know that I cannot hold them out as "contract" proofs. Just trying to make the best of an imperfect situation by asking if there is anything I can do to make sure the service bureau output is a realistic facsimile of the output of a press running the GRACoL profile (other than, obviously, making sure the service bureau understands I want a GRACoL proof!)

As long as you can get a GRACoL proof (and VERIFY that it's a GRACoL proof via measurement), you should be able to take that proof to any shop claiming to print to GRACoL specs and expect a reasonable match.....I say REASONABLE match because there are tolerances where they can deviate from GRACoL specs slightly and have the print run still be considered GRACoL.

Terry

 

[Greg Imhoff]

Hello Harvey - Gordo, Terry, Stephen, Terry etc are all "spot on" in answering your important question.

You may also visit this great site for more information What is GRACoL? | IDEAlliance this is a great tool that simply works as directed (certified) etc. You should then be fine.

 

[tlotzer]

How does one manage mixed images for GRACoL 2013 output?

How does one manage mixed images for GRACoL 2013 output?

Terry,

We recently changed our export pdf settings in Indesign to make Prinergy pdfs and are getting varying color separations on different operator's macs. When opening a client's Indesign file, we convert to the attached settings. Prinergy is set to do no color conversions. Are there any books, articles or online pdfs describing the correct handling of varying rgb, cmyk images packaged for Indesign, and mixed use PDF files to get the files processed from raw client files through proofing and plating.

i.e. If a client send untagged RGB, US Web Coated, or US Sheetfed profiled images, an Indesign doc, or a mixed pdf, do we convert each image to GRACol 2013.icc, convert the Indesign doc to the same, export (converting to same) rip through Prinergy (leaving color unchanged), proof through Oris Color Tuner to our Epson 9900 using onboard Spectorlino to a GRACol ICC, then plate using Prinergy's Imagesetter output plate profile for our Sheetfed presses.

Or should we make an unmanaged pdf, let Prinergy color convert to GRACoL?

 

[Stephen Marsh]

We recently changed our export pdf settings in Indesign to make Prinergy pdfs and are getting varying color separations on different operator’s macs.

This would appear to indicate that different operators are using different colour settings, rather than sharing/using a single Adobe Colour Setting File (.csf). Or perhaps different operators are using different PDF export settings?

When opening a client’s Indesign file, we convert to the attached settings. Prinergy is set to do no color conversions.

Below you mention untagged input files. In the case of your Photoshop Colour Settings screen capture, you are using Adobe RGB as the working RGB space. This may be appropriate for internal work, however for client supplied RGB is it a safe choice? There is not right or wrong answer, however I believe that it is generally safer to go with sRGB as the working space for untagged/non-colour-managed supplied “mystery meat” RGB data. EDIT: I just added a blog post to illustrate:

http://prepression.blogspot.com.au/2014/06/rgb-icc-profile-roulette.html

In your colour management policies, everything is set to convert. I personally don’t agree with this. I would set all three to “preserve”. If you had to convert, convert RGB, but probably not CMYK and Grey! Then the choice is to preserve or set to off. There are compelling reasons for using both workflows, with no right or wrong answer - it will depend on your workflow and needs a wider discussion.


Stephen Marsh

 

[Stephen Marsh]

tlotzer, did I help or confuse things for you?


Stephen Marsh