Slammer needs a rocket scientist

[Slammer]

Yesterday I was at a customer and faced a coundrum that had me scratching my head like a monkey trying to figure out a typewriter.


We were testing in the Sonora X
The problem is that in the specs the energy required to image this plate is in Mj/cm2 or milijoule per square centemeter, that would be 120 to 140 Mj/cm2.
All in all straight forward, however the settings in XPO are to be entered in milliwatt.
Now there are plenty of converters on the web but they all want to convert Milijoule per second to miliwatt as you would in electric power, but I need the conversion for pressure per cm2.

Anybody far cleverer than I have a solution?

Oh and by the way, what goes on under the hood, as in what happens in the CTP if you were to (totally hypothetically speaking, of course) "accidently" configure the plate settings in XPO to "positive" instead of "negative?"

 

[Magnus59]

If you configure as positive instead of negative, you would end up with a negative image, because you would be exposing the none image areas.
Sorry I can't help you with energy conversion

 

[Slammer]

If you configure as positive instead of negative, you would end up with a negative image, because you would be exposing the none image areas.
Sorry I can't help you with energy conversion

That´s the thing, you don´t end up with a negative image, as that is controlled by the RIP settings, if the RIP is set to positive you get a positive image on plate regardless on how you set the plate type setting in XPO, as far as I can figure out setting positive in XPO don´t have that large an effect on plate, I imagined that I could detect a slightly higher contrast on plate but I could be mistaken.

 

[Magnus59]

That´s the thing, you don´t end up with a negative image, as that is controlled by the RIP settings, if the RIP is set to positive you get a positive image on plate regardless on how you set the plate type setting in XPO, as far as I can figure out setting positive in XPO don´t have that large an effect on plate, I imagined that I could detect a slightly higher contrast on plate but I could be mistaken.

We changed from negative plates (Trillian) to positive plates (Electra XP) NO changes were made in the RIP, change was made to the plate type in the Magnus and then that plate type is selected in Xpo

 

[old guy]

https://www.dymax.com/images/pdf/technical_bulletins/lit135_intensity_conversion_chart_tb.pdf

is this what you need

 

[Deleted member 16349]

but I need the conversion for pressure per cm2.

? Pressure is normally force per area

Do you really want pressure per cm2 ?

 

[maxon]

I guess there's no way to translate the infrared power output (mW) into radiant exposure i.e. energy received by plate coating in Joules / sqcm unless you have access to a lookup table from the ctp manufacturer. Try to find out the coating sensitivity mJ/sqcm for a plate already calibrated on your or similar ctp and work from there. Make sure optics is clean and focus has been set up too.

 

[Slammer]

https://www.dymax.com/images/pdf/tec...n_chart_tb.pdf

is this what you need

It´s precisely what I need, it´s just that I spent the weekend with smoke coming out of my ears trying to figure out how to apply it.
It´s the time bit that gets me.

 

[Guest]

Setting this up would be trivial for your Kodak technician (or reseller depending where you are in the world). Less than an hour in-and-out including running a plate on the press to test development. That would be the easiest path to success I recon?

You need to input the mW and the drum speed would give you the time factor, but what speeds you can run the drum at will be influenced by the model and speed version of your specific machine. A Kodak technician will have the necessary calculator to work that out and set up your machine to delivery the maximum throughput.

 

[Slammer]

Setting this up would be trivial for your Kodak technician (or reseller depending where you are in the world). Less than an hour in-and-out including running a plate on the press to test development. That would be the easiest path to success I recon?

You need to input the mW and the drum speed would give you the time factor, but what speeds you can run the drum at will be influenced by the model and speed version of your specific machine. A Kodak technician will have the necessary calculator to work that out and set up your machine to delivery the maximum throughput.

Thanks, but Kodak techies only get out of bed if there is a SSL contract afoot, at least here abouts, and there isn´t. Anyway we figured it out and got exeptional results. Sadly the customer being conservative like most printers in Bavarian Congo went back to the old ways.
Ah well it was worth a shot.

 

[Guest]

Yeah, these things sometimes get turned around for reasons far removed from the technical merits.