CTP Plate Exposure Tolerance

[aqazi81]

What are the ISO Standard tolerance for thermal CTP plate, like 50% should measure 50 or do we have some tolerance of +/- 1 or 2 %?

 

[gordo]

What are the ISO Standard tolerance for thermal CTP plate, like 50% should measure 50 or do we have some tolerance of +/- 1 or 2 %?

AFAIK there is no ISO specification - and there shouldn't be. A typical vendor statement is +/- up to 2% at 50%.
As a single isolated metric it's not that important. If you're evaluating CtP you need to look at the totality of the imaging characteristic - not just one aspect.

 

[aqazi81]

We have set up a new CTP and plate is measuring 49@50% and 8.9 @ 10% and 75.5@ 75 %.. Is this ok? And what do you mean by imaging characteristics? Please explain a bit.
Regards

 

[gordo]

We have set up a new CTP and plate is measuring 49@50% and 8.9 @ 10% and 75.5@ 75 %.. Is this ok? And what do you mean by imaging characteristics? Please explain a bit.
Regards

What you're measuring is probably within the accuracy tolerance of the instrument you are using to measure the plate.
Other imaging characteristics like thermal compensation, geometric accuracy, plate to plate consistency, consistency between platesetters, plate to plate registration, etc. some of the things described here: http://the-print-guide.blogspot.ca/2010/07/choosing-ctp-some-considerations.html

If the platesetter is consistent you can use curves to have whatever tone value you want on the plate. Consistency is more important than accuracy.

 

[aqazi81]

Thank you very much Gordo for your quick reply.

Regards