Print Link settings for CIP3 data

[PixelNixie]

I will try to make this question as clear as possible. Is there a method for extracting the ink preset data from a .ppf file? I am trying to solve an issue with the ink key presets on a very old web offset press with a GMI Microcolor II interface and I am trying to determine the best interface settings to use in Print Link. I also need to compare the ink key presets in the file going from Prinergy to the CIP3 interpreter to the press so I can make sure there isn't something else going on with the very old computer setup. When I configure Print Link with a manual .txt configuration I can see clearly what the ink presets are but not with a .ppf file. I have tried using PressPerCent to inspect the .ppf file but ithat software does it's own ink preset calculations that don't match the numbers I am getting at the press.

 

[Magnus59]

I will try to make this question as clear as possible. Is there a method for extracting the ink preset data from a .ppf file? I am trying to solve an issue with the ink key presets on a very old web offset press with a GMI Microcolor II interface and I am trying to determine the best interface settings to use in Print Link. I also need to compare the ink key presets in the file going from Prinergy to the CIP3 interpreter to the press so I can make sure there isn't something else going on with the very old computer setup. When I configure Print Link with a manual .txt configuration I can see clearly what the ink presets are but not with a .ppf file. I have tried using PressPerCent to inspect the .ppf file but ithat software does it's own ink preset calculations that don't match the numbers I am getting at the press.

When you export the Printlink data as a manual text file, you specify the number of ink zones etc.
That data is not included in the .ppf file as the ink zone data is calculated by your press interface which splits the ppf into ink zones as defined for the press, therefore that data is not included in the ppf. The values will also be affected by any curves you have applied at the press interface.

 

[PixelNixie]

When you export the Printlink data as a manual text file, you specify the number of ink zones etc.
That data is not included in the .ppf file as the ink zone data is calculated by your press interface which splits the ppf into ink zones as defined for the press, therefore that data is not included in the ppf. The values will also be affected by any curves you have applied at the press interface.

That makes perfect sense, thank you. There must be an issue with the interface or the old CIP3 interpreter and not my Print Link settings. That is at least one variable I can rule out for now.

 

[turbotom1052]

I will go out on a limb here and say this.... If the press is as old as you say it is, I seriously doubt that you will benefit all that much from the use of CIP3 data, even if you could import the PDF file into the RIP software. If your thoughts are that by providing the press with the ability to get accurate ink fountain settings via a software based interface, will cut down on makeready times, I think you will be disappointed. Ive found that even on state of the art equipment, CIP data is at its best, only a starting point to accurate ink fountain settings. My feeling is that if your looking for modern technology to breath new life into antiquated equipment, your chasing your tail. I know its not what you really want to hear but its how I see it. Your efforts and money would be better spent finding an old school fully experienced pressman to run your equipment!!! The money you spend on such a person will be quickly recovered in waste savings alone, with the added benefit of a quicker make ready and improved print quality.

 

[PixelNixie]

I will go out on a limb here and say this.... If the press is as old as you say it is, I seriously doubt that you will benefit all that much from the use of CIP3 data, even if you could import the PDF file into the RIP software. If your thoughts are that by providing the press with the ability to get accurate ink fountain settings via a software based interface, will cut down on makeready times, I think you will be disappointed. Ive found that even on state of the art equipment, CIP data is at its best, only a starting point to accurate ink fountain settings. My feeling is that if your looking for modern technology to breath new life into antiquated equipment, your chasing your tail. I know its not what you really want to hear but its how I see it. Your efforts and money would be better spent finding an old school fully experienced pressman to run your equipment!!!

This is not new or modern technology for us, the press interface has been running this setup for a long time. Yes, it is extremely old but the whole system is old, I am not adding any new tech into the mix nor am I trying to breathe new life into anything, I am well aware of the limitations of equipment this old. I am simply trying to figure out why the ink key presets at the press do not match the calculations done by Print Link and see where in the system settings could be adjusted for a more accurate starting point. Our head pressman has been running this press for 35 years and we have have several other "old school" pressmen on staff as this this is not our only old press it is simply the only one with this interface. I admit that my color management expertise stops up river of the press interface/ink presets. It is more of a side project that came up while I was analyzing data for our plate curves.

 

[turbotom1052]

This is not new or modern technology for us, the press interface has been running this setup for a long time. Yes, it is extremely old but the whole system is old, I am not adding any new tech into the mix nor am I trying to breathe new life into anything, I am well aware of the limitations of equipment this old. I am simply trying to figure out why the ink key presets at the press do not match the calculations done by Print Link and see where in the system settings could be adjusted for a more accurate starting point. Our head pressman has been running this press for 35 years and we have have several other "old school" pressmen on staff as this this is not our only old press it is simply the only one with this interface. I admit that my color management expertise stops up river of the press interface/ink presets. It is more of a side project that came up while I was analyzing data for our plate curves.

So your saying that this has in the past been a working system that has seemed to drift off of its previous accuracy? If so then you need to think about what has changed that would account for such a drift. One thing that comes to mind is the ink fountains zero set has changed as they often do. The next thing might be to look at the possibility of out of adjustment rollers, or worse yet rollers worn beyond their useful life. I say this because its been my experience that a company that doesn't stay abreast of the latest technology often, and I stress the work often as opposed to always, winds up trying to put lipstick on a pig. Not suggesting that this is you or your company but I have seen that dynamic more times than I care to count. I apologize if I have offended your sensibilities but just sayin.

 

[PixelNixie]

So your saying that this has in the past been a working system that has seemed to drift off of its previous accuracy? If so then you need to think about what has changed that would account for such a drift. One thing that comes to mind is the ink fountains zero set has changed as they often do. The next thing might be to look at the possibility of out of adjustment rollers, or worse yet rollers worn beyond their useful life. I say this because its been my experience that a company that doesn't stay abreast of the latest technology often, and I stress the work often as opposed to always, winds up trying to put lipstick on a pig. Not suggesting that this is you or your company but I have seen that dynamic more times than I care to count. I apologize if I have offended your sensibilities but just sayin.

This doesn't offend my sensibilities it just isn't relevant to my original question which said nothing about color accuracy or a problem with the press itself aside from it being an older interface. My original question was really about where/how to find the relevant ink preset data in the files being set to to the press. The system itself is working just as it always has but during my investigation into some other links in out process control chain I noticed that the ink key presets seemed quite high and do not match the calculations I get from manual files in PrintLink or from PressPercent. Since my expertise is mostly in prepress, process control and data analysis rather than the press room I was mistakenly thinking that the ink key preset data was in the .ppf file like it is in a manual file. After getting a better understanding of how that data is processed, it is now clear that those presets are being calculated downstream of PrintLink and are happening at the CIP3 interpreter and/or the press interface itself. The actual press is fine and is maintained in a stable repeatable condition as per the basic principles of process control, it is also my pet project as most of our equipment is fully upgraded and generally takes care of itself with minimal effort.

 

[turbotom1052]

This doesn't offend my sensibilities it just isn't relevant to my original question which said nothing about color accuracy or a problem with the press itself aside from it being an older interface. My original question was really about where/how to find the relevant ink preset data in the files being set to to the press. The system itself is working just as it always has but during my investigation into some other links in out process control chain I noticed that the ink key presets seemed quite high and do not match the calculations I get from manual files in PrintLink or from PressPercent. Since my expertise is mostly in prepress, process control and data analysis rather than the press room I was mistakenly thinking that the ink key preset data was in the .ppf file like it is in a manual file. After getting a better understanding of how that data is processed, it is now clear that those presets are being calculated downstream of PrintLink and are happening at the CIP3 interpreter and/or the press interface itself. The actual press is fine and is maintained in a stable repeatable condition as per the basic principles of process control, it is also my pet project as most of our equipment is fully upgraded and generally takes care of itself with minimal effort.

On a modern printing press, and I will just use Heidelberg as an example, only because im most familiar with them, there is a setting in the presses interface called "characteristic curves". This setting is where you go to make the sort of adjustments that you seem to be talking about. What im getting from your postings is that this old press has been retrofitted with an aftermarket system. Am I correct in this assumption? Not sure if an older inking retrofit would have that level of adjustability but perhaps you can contact the manufacturer (if they are still in business) and inquire. Its been my experience that often pressroom employees do not fully utilize all the technology thats available to them.

 

[jshawy]

I will try to make this question as clear as possible. Is there a method for extracting the ink preset data from a .ppf file? I am trying to solve an issue with the ink key presets on a very old web offset press with a GMI Microcolor II interface and I am trying to determine the best interface settings to use in Print Link. I also need to compare the ink key presets in the file going from Prinergy to the CIP3 interpreter to the press so I can make sure there isn't something else going on with the very old computer setup. When I configure Print Link with a manual .txt configuration I can see clearly what the ink presets are but not with a .ppf file. I have tried using PressPerCent to inspect the .ppf file but ithat software does it's own ink preset calculations that don't match the numbers I am getting at the press.

The CIP3/.ppf data from CTP is a Standard and Raw Data file. Its normally a 3 step process from the CTP to the press.

1. Kodak Printlink generates CIP3/.ppf raw data file . Ink key zone percentage presets cannot be seen here. It is just image/separation data for the Front and Back. See picture. This is then sent to a prepress interface for processing.
2. The prepress interface will generate its own .ppf with ink key zone presets and number of ink zones depending on which printing press it is for. The ink key zone percentage preset values can be seen in this .ppf. See picture.
3. The press console(GMI microcolor?) will then preset the ink key positions with manipulation/optimization from this new .ppf file. This .ppf file should be located on some harddrive at the press console waiting to be used for the presetting.

I don't know the GMI microcolor system but i would believe there should be some way of optimizing the .ppf ink zone values before presetting the ink keys. The GMI microcolor maybe limited in what it reads and manipulates from the .ppf ink zone values and sometimes you just have to be happy you with what you get.

There are also many variables on each individual web offset press that can effect the ink key opening positions.

• Inks - different inks will require different ink key openings depending on their pigment strength.
• Ink key zeros.
• Ink duct fountain roller speed - a speed change will change the ink key opening positions. Does the GMI mircocolor preset the ink fountain roller speed depending on .ppf coverage percentage?
• Ink roller condition and settings.
• Ink transfer from ink duct fountain roller - is the web press a ductor roller or film roller for transfer to the ink roller train? The film roller setting can change the ink key openings significantly, depending on how close or how far it is set to the ink duct fountain roller.
• Paper type - different paper stocks require different amounts of ink film. Newsprint typically requires 30% more ink than a high GSM coated stock. Does the GMI microcolor have a paper type option before preseting ink keys?

Example of ink zone coverage data from .ppf, ink key preset from console and the actual recorded values.