ECRM Mako 4x, G&J processor, AGFA Chemistry Questions

[ighodaro]

Our office uses an ECRM Mako 4x CTP, Glunz and Jensen Processor, AGFA Chemistry.
It is just 4 months old and we are quite new to the technology.
As manager, I have a couple of questions to ask, I need clarification.

We use Coreldraw X7 to send jobs to the Rip server, we first use either one of these methods.

1. Convert to Bitmap, then export as PDF, then send to Ripserver
2. Export as TIFF, open COREL PHOTO PAINT, spilt image as CYMK, then export to PDF, then send to Ripserver (This method images faster than the first method)

But we noticed in both methods, we have darker images after press, than those brought on the computer. So we have to brighten the pictures on the computer before we send it and customers do not desire this.

Please I need your help.
I have other questions though, but l begin with this one.

 

[gordo]

Our office uses an ECRM Mako 4x CTP, Glunz and Jensen Processor, AGFA Chemistry.
It is just 4 months old and we are quite new to the technology.
As manager, I have a couple of questions to ask, I need clarification.

We use Coreldraw X7 to send jobs to the Rip server, we first use either one of these methods.

1. Convert to Bitmap, then export as PDF, then send to Ripserver
2. Export as TIFF, open COREL PHOTO PAINT, spilt image as CYMK, then export to PDF, then send to Ripserver (This method images faster than the first method)

But we noticed in both methods, we have darker images after press, than those brought on the computer. So we have to brighten the pictures on the computer before we send it and customers do not desire this.

Please I need your help.
I have other questions though, but l begin with this one.

1-Define/choose a standard for your printing
2-Calibrate your computer's display
3-Choose the appropriate profile(s) so that you display simulate that standard
4-As needed curve the bitmaps to normalize the dot gain to your standard (normally that would be done to the contone images before they are bitmaps - i.e. "plate curves")

 

[ighodaro]

Thank you for your response Mr gordo.
I find your response valuable.

As per 1( Defining/choosing a standard for printing), we don't print all jobs ourselves, most of the prints are done by independent printers who come to use our machine for the service or KORD machine operators who use different inks with different standards.

How do we address this?

I appreciate your anticipated response

 

[ChrisZ]

First of it all you need to linearize your imager and plates.
Expose test strip on the plate.
1, 2, 3, 5, 7, 10, 15, 20, 25, 30, 35, 40, 45, 50, ............, 95, 97, 98, 99, 100% tint.
On non calibrated plate 50 should be 55-57% Adjust expose power to achieve that.
Measure that plate and create compensation curve for your plates.
Normally you apply that in the rip software.
Dotgain on the press is another story...
Chris

 

[gordo]

First of it all you need to linearize your imager and plates.
Expose test strip on the plate.
1, 2, 3, 5, 7, 10, 15, 20, 25, 30, 35, 40, 45, 50, ............, 95, 97, 98, 99, 100% tint.
On non calibrated plate 50 should be 55-57% Adjust expose power to achieve that.
Measure that plate and create compensation curve for your plates.
Normally you apply that in the rip software.
Dotgain on the press is another story...
Chris

In the majority of cases it's not necessary to linearize plates before creating and applying a dot gain compensation curve. It is a redundant step that can lead to errors. Just calibrate the plate (correct exposure and processing) then create a dot gain compensation curve for the press. ( http://the-print-guide.blogspot.ca/2010/10/to-linearize-your-ctp-plates-or-not.html )

 

[ChrisZ]

Gordo violet process is highly unstable, so I always recommend to linenarize plates first than review all workflow.

 

[gordo]

Gordo violet process is highly unstable, so I always recommend to linenarize plates first than review all workflow.

I don't see how the instability would make any difference at all. Maybe you could describe what steps would be taken with and without linearization.

 

[maxon]

Violet plate processing is as stable as you care keeping the machine within specs. I agree violet processors do need more maintenance than others but again, has nothing to do with stability.
Linearization is the way to go. The man says they have a prepress bureau there, no offset machines of their own. Wouldn't recommend using any Corel above X4 unless they have harlequin v.9 at least.
ighodaro, read the rip user guide to learn how to calibrate your plates and control your process.

 

[gordo]

Violet plate processing is as stable as you care keeping the machine within specs. I agree violet processors do need more maintenance than others but again, has nothing to do with stability.
Linearization is the way to go. The man says they have a prepress bureau there, no offset machines of their own. Wouldn't recommend using any Corel above X4 unless they have harlequin v.9 at least.
ighodaro, read the rip user guide to learn how to calibrate your plates and control your process.

Please explain why linearization is the way to go.

 

[ighodaro]

Wow, Thank you gordo, ChrisZ and maxon for your valuable response.

I will try them out independently and give you feedback on the outcome.

I still look forward to further contributions from you and other members.

Thank you very much once again.

 

[gordo]

Wow, Thank you gordo, ChrisZ and maxon for your valuable response.

I will try them out independently and give you feedback on the outcome.

I still look forward to further contributions from you and other members.

Thank you very much once again.

It would be great if they could answer my simple question :-(

 

[ChrisZ]

Please explain why linearization is the way to go.

Because after every chemistry change and processor cleaning you have to create curves again.
Way I explained you linearise plates leaving press curves untouched. Pretty simple and not time consuming.
Way you suggested after processor cleaning you need to create curves for every printing machine and substrate combination.
Chris