WTF is wrong with kodak dealers?

C

cementary

Well-known member
I just can't understand this s**t:
Our company is moving toward process free sonora plates and our dealer sent their tech specialists to made some tests.
The first thing they said is – you need to increase pre-damp on your press in order to clean the plate. WTF??? Official kodak white paper very CLEARLY claims that there is no need in pre-damp increasing. In fact it claims that pre-damp increase is wrong and leads to increased dampening contamination.
Second they've told that after setting up ctp profiles they need to linearise plate. LINEARISE, Karl!
Sonora plate linearisation – it's some kind of oxymoron or smth? For what the hell do anyone need this?

So what, kodak tech spec don't RTFM?
 
No idea on the pre-damp but why would you think you do not need need a linear plate to start with?
 
Hi cementary, If you look at "pre-damping", this will wash out the plate and all the blue coating will go back into the fount system. I have washed a single plate out today and believe me, there is quite a discolouration from the coating that comes off. Best way in my opinion is to start press up as normal, and in theory the first 10-20 press impressions should transfer the majority of coating to the blanket and substrate.
 
gordo said:
Could you explain why you think you need a linear plate to start with?
Click to expand...

To make sure you are starting with a plate that reads what it should. Now I've never used processless plates before but I still think you would want to start with a plate where the dot percentages are correct? Correct me if I'm wrong though.
 
Last edited:
Print Monkey 63 said:
Hi cementary, If you look at "pre-damping", this will wash out the plate and all the blue coating will go back into the fount system. I have washed a single plate out today and believe me, there is quite a discolouration from the coating that comes off. Best way in my opinion is to start press up as normal, and in theory the first 10-20 press impressions should transfer the majority of coating to the blanket and substrate.
Click to expand...
That's exactly what official kodak papers claims. Just to start press as usual. I wonder why kodak technics don't read them.
 
gordo said:
How does no deviation in dot translate into needing to linearize the plate?
Click to expand...

Good to see you in another kodak thread.
I know your position about two curve workflow. And i can't argue that for sure))).
In our prepress department with plate linearization we trying to solve deviation between 2 ctp with different-time for washing bath (sunday for one, wednesday for another).

By the way, gordo, do you know that kodaks partner place referres to you site when explaining device output resolution and gray levels?:)
 
cementary said:
Good to see you in another kodak thread.
I know your position about two curve workflow. And i can't argue that for sure))).
In our prepress department with plate linearization we trying to solve deviation between 2 ctp with different-time for washing bath (sunday for one, wednesday for another).

By the way, gordo, do you know that kodaks partner place referres to you site when explaining device output resolution and gray levels?:)
Click to expand...


No, I did not know that. LOL What is the Kodak partner place?

When I saw the title for this thread "WTF is wrong with kodak dealers?" I thought of a local newspaper that has been trying to get Kodak to contact them about implementing inkjet in their daily newspaper work. Kodak hasn't even returned their calls.

I still get a kick out of Kodak still using the graphics I did some 15 years ago. And also that no one in marketing seems to bother viewing the Kodak website for the products and solutions they're supposed to be promoting. For example, here is the web page for one of Kodak's signature technologies:

Kodak%20webpage_zpsx7m4qiby.jpg

It's been that way for a few years - and there are other pages just like it on their website.
 
alibryan said:
As far as linearizing your plates (initially, for testing), I'm sure they need to test your imaging laser's strength to the new plates and want to be sure everything is correct before applying the curve.
Click to expand...


Unless things have changed dramatically since I worked at Creo/Kodak - linearizing has nothing to do with calibrating the laser/imaging system.

It's also best on ctp plates (if possible) to put a test strip on your plates in a non-printing area and image it on all your plates, so you can scan it anytime you like to check for correct imaging. The strip should have one half linearized, and one half with curve applied for comparison purposes.
Click to expand...

The use of the strip is correct - however there is no need for the reference half to be linearized. The reference file should be a bitmap (so it doesn't get screened or curved by the RIP) of the tone reproduction curve rendered as a step wedge. The bottom half is contone so that it is affected by whatever plate curves you normally use. If you can't distinguish the two then the correct tone reproduction curve has been applied.

That being said there are some exceptional cases where using a curve to linearize the plate and then applying another curve on top of that may be appropriate - but it is the exception.
 
alibryan said:
So you're saying that the two being indistinguishable, is that visually? The strip(s) I've seen are step wedges with one side being linear, and the other being curved. They're right next to each other all the way up on a strip and both sides are measured with an electronic scanner, and are definitely different from one another.

These strips are to check the quality of the image on the plate and to be sure that everything is within tolerance.
Click to expand...


Visually to quickly see if the right curve was applied. Measured if desired to confirm correct plate exposure.
 
alibryan said:
Years ago I ran Kodak process free plates on both a Heidelberg, and a Komori. On the Komori (Komorimatic) we would drop the damps for 20-25 revolutions and then start printing, no problem. The Heidelberg (alcolor) was a little more sensitive to the plates and sometimes would take up to 40 revolutions before entirely cleaning up for print. After initial 'pre-damp' - 10-15 seconds - both presses were ready to print and the plates ran great. I'm pretty sure the reason why the Heidelberg was more sensitive on start up was because most Heidelbergs run their water system integrated. Either way, since these plates are process free, the coating that's still on them needs to go somewhere, so requiring pre-dampening on them isn't all that surprising. What's the big deal?
Click to expand...

If something worked years ago, that doesn't mean it should work nowadays. I believe that not all experience is a good and "all-time woking" experience.
In fact kodak tech specialist told me quite the same: that he had been working with process free plates for years and he knows what to do best.

Pre-dump increase isn't required with sonora xp plates. I'll quote some from Kodak official white paper:
"However, some printers have tried to “improve” the image preparation process by changing their press settings, and this practice could cause problems. Printers that don’t understand how the image is prepared on Sonora Plates sometimes think that they need to increase the pre-damp to “develop” the plate on press, particularly if these printers have had experience with inferior process-free plates. However, excessive pre-dampening can cause contamination of the fountain system. After a proper level of pre-dampening, the coating is still on the plate."

See the attached file for more info.

So, my answer for "What's the big deal?": it's not a big deal, it's just stupid not to follow producer's recommendations.
 

Attachments

  • No Press Contamination white paper_Aug2013.pdf
    586.7 KB · Views: 278
You must log in or register to reply here.

Similar threads

Revolutions
Kodak Sonora X - DOP issues
Replies
18
Views
6835
Revolutions
Revolutions

PressWise

A 30-day Fix for Managed Chaos

As any print professional knows, printing can be managed chaos. Software that solves multiple problems and provides measurable and monetizable value has a direct impact on the bottom-line.

“We reduced order entry costs by about 40%.” Significant savings in a shop that turns about 500 jobs a month.

Learn how…….

   
Back
Top