Stepped Images not having identical dot structures (follow-up on another forum)

[kewlbigdan]

In investigating a inconsistent print issue, an extreme fine view was put on the dot pattern of our Stepped images.
The outside expert said these stepped images should be identical dot for dot. I have to admit I cannot remember from my experience if we always had 1 to 1 dots on stepped images.
Will this cause issues? (see attached)

Esko says it is currently not available in IE that we must use FlexRip.

 

[gordo]

Question - What screening system are you using?

- Just noticed that you've got multiple posts on your issues with different info in each. Very confusing (for me anyway) - elephant and the blind men syndrome.

 

[SteveSuffRIT]

The image is 4 around.
Is the color shift always in the same position or does it move around during the production run?
If it moves around it may be a rosette/moire pattern from misregister?
Steve Suffoletto

 

[helloWorld]

@SteveSuffRIT What are you using to step your file?

There are two options inside of Plato (and I think somewhere in Automation Engine if you are using AE to step). Make sure you check the option 'Reset for each external file' if you want exact screening on each repeat.

 

[kewlbigdan]

Thanks everyone for your responses. Gordo I will have to look up the blind elephant man syndrome. sorry for the confusion. You would one of the reasons I posted it here as you have had great insight into color in the past for me.
Steve, the image to image hue shift followed the plates.
Till, We are using Esko Imaging Engine. According to ESKO R&D, the Screen Registration function is slated for the Nov 2020 release and currently works only on the older FlexRip. I still don't see this as a major contributor.
It was determined today, we had installed LED lighting about the press and not shielded the lights. This could be drying out the ink or hardening the plates when the press is idle.
It was also found the mounters were reusing stickleback and overlapping it as well. Lets not go there. I have no words.

 

[chriscozi]

First thoughts on cursory inspection of the close up dots - the image is already dots before you rip them to the press.
This leads to inconsistent dot patterns between the stepped images.
If your starting image is already rasterized, not a contone, this could happen.
YMMV

 

[gordo]

First thoughts on cursory inspection of the close up dots - the image is already dots before you rip them to the press.
This leads to inconsistent dot patterns between the stepped images.
If your starting image is already rasterized, not a contone, this could happen.
YMMV

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