discrepancies in PDF display

[Dario]

Hello everyone,
I have a pdf which is shown in 2 different ways: in Acrobat (and also Illustrator) I see it as I would like (full red) while ArtPro+ and PackZ show it differently (red & magenta).
It's simply an almost white object overprint over a colored one.
Does anyone want to help me understand what it depends on?
(the pdf file is attached)

Acrobat (& Illustrator)

ArtPro+

PackZ

 

[johnny_jay]

It the overprint settings where each is being viewed.

 

[Dario]

It the overprint settings where each is being viewed.

sorry, but I don't get your answer - the Acrobat screenshot was taken using overprint preview already ON

 

[johnny_jay]

I would say that Acrobat views the file properly and the other two products do not. How does the file attached appear in ArtPro+ and PackZ?

 

[kslight]

I would say that Acrobat views the file properly and the other two products do not. How does the file attached appear in ArtPro+ and PackZ?

This…sometimes we have customers with this question and it’s always..they are using their phones and or a non Adobe viewer.

 

[Dario]

I've already posted screenshots for all the three situations - Acrobat, PackZ and ArtProPlus - in my first post.

 

[bill kahny]

Check the overlay settings in all the programs! What you posted looks correct in acrobat and not in the other two or are you saying you want the box there?

 

[Dario]

or are you saying

in Acrobat (and also Illustrator) I see it as I would like (full red)

 

[Dario]

could one of you really kind rip the pdf in question using your software and tell me whether the result is all full red or not?

 

[Stanislav Rakov]

Wow, interesting bug or fitch that would allow observers to see the difference.

 

[johnny_jay]

With my normal settings I get a big white box - I see the pdf has layers

If in my color convert i change overprint mode, I get a pink box.

Prinergy 9.5

What is the intent of how this file is supposed to print?

 

[DP Prepress]

Instead of a .1% Yellow box set to overprint 100M 100Y,

Maybe try a .1% Yellow box set to darken (or multiply).

Artpro+ seems to be using the yellow value from your .1%Y box and overriding the 100% yellow underneath when the illustrator file is set to overprint.
I get a more uniform preview of this file across different applications using darken.

I'm still not exactly sure why anyone would need an (almost) white box to overprint 100M 100Y ...
It seems like just deleting the .1%Y box would have the same effect.

Regards,

 

[Glenn McDowall]

If the colors were DeviceN then the .1% Yellow would knock out the 100% Yellow despite it being set to overprint.
Also a 0% (DeviceN) Magenta would knock out the 100% Magenta even if was set to overprint.
0% of a DeviceN color set to Overprint is a common way of knocking out the same color but not affecting any other DeviceN color for manual trapping.
Its not actually possible to print 100.1% of a colour without using two plates so it makes sense.

With CMYK the rules are different.
When set to 0% and overprint any of the 4 channels will not punch out of CMYK but the 0.1% yellow should punch out of the Yellow. The downside of this is that a cmyk white object set to overprint will not appear on your print. Most RIPs will have a setting to "fix this" and force these objects to KO.

If the pdf describes one of the two objects as DeviceN and the other as CMYK then even though both are called Yellow they are technically seen as separate channels so on screen a DeviceN object could actually overprint a cmyk object, so thats the simulation you see.

When you convert a spot color to cmyk, you'd normally have to simulate the overprint to keep the same visual appearance, especially with transparency , that doesn't necessarily happen when the DeviceN is one of the process colors.

 

[PeteKincaid]

When I open it up in packz, I see the same thing. I believe what is happening is the yellow in the top object is overwriting the 100% yellow in the bottom object which is set to be (100m100y). If you make the bottom object 100m you will notice that the color is pretty much identical as the top object (100m .1y)

I found this online, it makes sense when looking at your file.

• If Overprint is ON and Overprint Preview Mode is ON, then every object that is painted removes any previously painted color in the same area and in the same color space - but only if it has more than 0% in the respective colorant. That means the Cyan text knocks out every previously painted Cyan object but previously painted Yellow (and Magenta or Black) remains (is overprinted) as can be seen in the image at the bottom.

I also ran this through the cloudflow rip and the results where the same as I am seeing in PACKZ. I think Adobe is displaying this wrong.

 

[Dario]

That PDF I posted is based on the same concept as the 'PDFviewerCheckerVIGC' - but when I noticed those differences in the display, I got worried.
It is obvious that someone among the various software (rip, editor, viewer, ...) does not show the PDF correctly, but which one?
I am quite concerned that perhaps it is Adobe that is showing it the wrong way, considering that its software is much more widespread.

 

[PeteKincaid]

@Dov Isaacs
Not sure if you can give any input into this issue?

 

[Dario]

this is the response from a HYBRID tech:
"the issue occurs in illustrator and acrobat with percentages below 1%.
if in the same file you raise the percentage of yellow to 1% the display will change in both illustrator and acrobat."
(...and therefore Adobe is to blame)

 

[bill kahny]

Since no device can hold a 1% dot isn't acrobat displaying what you get when you print it?

 

[Glenn McDowall]

Using Pitstop I tried increasing the % yellow in 0.01 increments at 0.2% it behaves as expected and displays the same as it does in Art Pro.
The same is true through Prinergy.
I'm guessing that Adobe doesn't round up the really small %age and treats it as 0%.
Since Prinergy has an Adobe Core it behaves the same as Acrobat?
Not sure how this helps you since you wanted the Acrobat result.

 

[Dario]

Yes, even I noticed that the "problem" in Acrobat occurs only with a percentage of yellow below 0.2%.
From 0.19% and below the display problem appears.
I know it is not a "big" issue, however I am glad we investigated it.
...And to answer another question: that gizmo is for me to have my users check that they are viewing the PDF with a proper viewer.
(see attached pdf)