Prosetter 74 CtP - Imaging non-image areas...help!

karish552

karish552

Active member
I've been using a Heidelberg Prosetter 74 30mW laser with Violet photopolymer plates for over 2years. Suddenly over night, the CtP has started imaging non-image areas when we attempt to burn plates. I've verified that the processor is working correctly and have cleaned the optical head and rotating mirror on the CtP. It seems to me that the CtP doesn't recognise the non-image areas of the artwork and the whole page appears green after processing the plate whereas areas outside the artboard remain white!

Any ideas how I can resolve this issue? :confused:
 
I imagine you have tried the test with several different files output with different applications.
What RIP is driving the platesetter?
It sounds more like a problem with the RIP sending the incorrect data since you see the "page boxes."
You have restarted your RIP server and had no effect?

MSD
 
karish552 said:
I've been using a Heidelberg Prosetter 74 30mW laser with Violet photopolymer plates for over 2years. Suddenly over night, the CtP has started imaging non-image areas when we attempt to burn plates. I've verified that the processor is working correctly and have cleaned the optical head and rotating mirror on the CtP. It seems to me that the CtP doesn't recognise the non-image areas of the artwork and the whole page appears green after processing the plate whereas areas outside the artboard remain white!

Any ideas how I can resolve this issue? :confused:
Click to expand...

The problem is from the Type of working plates picked in the RIP or the console. I do not know what kind of RIP you are using. The Violet PhotoPolymer plate is a positive working plate. If you clicked the negative plate you will have to correct the setting.

Hope this will help!
 
Karish, give us details about the rip you have and interface.
All violet photopolymer plates are negative, laser writes the image. As Farshad said it may be a setting in your Metashooter ... among many other reasons unfortunately.
 
Thank you for the feedback.

I am using a Xitron Harlequin RIP which is connected directly to the CtP via a Xitron interface, so the Metashooter is not being used. This has been working well for over a year now. I tried running a test exposure from the CtP Speedway Engine and the result is the same, so whether it's sent through the RIP or the CtP software it is still burning non-image areas.

The plates I'm using are Negative Violet, Fuji LP-NV, and I verified the settings are set for Negative violet. I've tried restarting the RIP as well.
 
maxon said:
My guess the laser is gone doesn't switch off anymore. Call service.
Click to expand...

Thanks for the feedback Maxon, is there anyway I can run some tests or confirm for sure that it is the laser that is gone? I did try to reduce the burn resolution and the green areas fade somewhat but still not as it should be.
 
Hello karrish 552,

How about your Prosetter? Did you try set your Rip setting to positive and expose a plate and see
whether the image is correct now...
I think it shouldnt be the laser faulty if the laser will write the non image area and switch off at the image
area...
 
I don't think the problem is with the laser, most seem to be a problem of focus, could you verify if the plate is well fixed in the internal drum?

karish552 said:
I've been using a Heidelberg Prosetter 74 30mW laser with Violet photopolymer plates for over 2years. Suddenly over night, the CtP has started imaging non-image areas when we attempt to burn plates. I've verified that the processor is working correctly and have cleaned the optical head and rotating mirror on the CtP. It seems to me that the CtP doesn't recognise the non-image areas of the artwork and the whole page appears green after processing the plate whereas areas outside the artboard remain white!

Any ideas how I can resolve this issue? :confused:
Click to expand...
 
Thanks for the response, At this point my CtP is still down.
I did try a focus test and focus adjustment but the result is the same. I also tried changing RIP settings to positive also had the same results. I ran the CtP with covers off and verified that the plate is sitting well in the internal drum.
 
White area is not exposed by laser. So check expose test of laser power and check working area of power for polymer plate in GUI. It must be not bottom (bottom is for silver plate)
 
_Valery_ said:
White area is not exposed by laser. So check expose test of laser power and check working area of power for polymer plate in GUI. It must be not bottom (bottom is for silver plate)
Click to expand...

Is there a parameter called "BIAS"? If yes, then maybe the value is too high...
 
Hello Karish552,

Is your computer have GUI software? Graphic user interface for Prosetter?
If yes, 1) There is a plate call INPUT to set your plate setting like focus, laser power and polarity, pls check the
polarity is Negative.
2) you can try to reload the Prosetter backup file (machine parameter) to Prosetter.
If you dont know pls private message to me.
 
karish552 said:
I found the BIAS parameter, what should the value be?
Click to expand...

Don't remember the default value (is it written somewhere?)
Go down with the value - bias is the power for laser diode that should NOT expose the plate - it's for speed up diode-driver response.
Good luck
 
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