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Pierhouse
11-27-2009, 09:02 AM
Hi

We have recently purchased a Xerox 700 with external EX Print Server. I've been landed with the job of setting up our SOP's for using the printer and I am looking into the calibration stage.

I have been following the EFI Calibration How To Guide and I am not entirely sure if the Measurements vs Target graph (attached) is telling me that my engine is ok or that I have a problem.

My understanding is that if the measured curve is above the target curve that is not necessarilly an issue unless it is more than 10% above the target.

My measured curve is showing to be over 10% out above the target curve for all colours between 50% and 80% input so should I call for a service visit as there is a problem with the engine? (Not that I know what "input" is referring too!!)

Is this correct or have I misunderstood the guide? Any help would be much appreciated?

Thanks in advance

Graeme

Brian_S
11-27-2009, 12:08 PM
Your curve response for that machine sounds just about right. The 10% rule applies to 100% input, the maximum density that the printer is able to achieve for Cyan Magenta Yellow and Black. If your "thin line" is above your "thick line", then you should be good to go (within 10% of course).

A little background if you are interested:
The thin line (or measurement) represents the engines raw density response. The thick line (or target) is the calibrated response. As long as the engine can achieve the maximum density, the Fiery calibration will adjust the raw response to the target curve. This target is the state in which the output profile was created. Calibration returns your engine to this profiled state. The 10% rule is to assure that calibration isn't causing the solids to be halftoned where it becomes visible.

Hope this helps.
thanks.

Pierhouse
11-30-2009, 03:06 AM
Thank you for your reply Brian. Can I just confirm that what you are saying is that the 10% rule only applies to the 100% input. So even though at 100% input my measured density is slightly below the target density, because it is less that 10% below there is no problem.

Thanks for your help so far.

Brian_S
11-30-2009, 09:15 AM
The 10% rule only applies if you measure OVER the desired density. I'm unable to open your word file, however if you are only slightly below the target density, you should be fine.

Pierhouse
12-01-2009, 02:38 AM
Hi Brian

Thank you once again for your help. I've attached my file as a jpg so hopefully it can be opened now.

oxident
11-05-2010, 06:55 AM
I'm facing the same problem and I'm quite sure I'm not inside the 10% tolerance region ... shall I ask Xerox to send me a technician in order to adjust the colors manually?

Please the attached image.