Web UI: "PANTONE Black 6 C" Color Error

[Sebastian37945585vyxu]

In the Acrobat browser Plugin (aka "Web UI") some "PANTONE Black" color variants are being displayed with wrong color values.

Attatched is an example PDF "test_B6C.pdf" where the Text was given the pantone color "PANTONE Black 6 C". It is displayed bright red, while the Acrobat color setting says it is Cyan (see screenshot "test_B6C.png"). But the original "PANTONE Black 6 C" should be a black color.

Using "PANTONE Black C" the effect is that the Acrobat browser Plugin (aka "Web UI") displays the color as white, while claiming the color would be bodeaux red.

(This bug only occures in the browser Web UI, the Acrobat Reader Desktop App displays the PANTONE Black colors just fine.)

Is this a known bug?
Is there a solution outside of refraining from using these "PANTONE Black" colors?

[Meenakshi Negi]

Hi Sebastian37945585vyxu,

Thank you for reaching out.

Please let us know if this happens when the text is added in Acrobat or another application. Share the steps used here to create the PDF and add the text. Once you share the information, we will replicate the behavior. 

Share the application and browser used. Check if you can replicate this behavior on alternate browsers.  

Thanks,

Meenakshi

[Sebastian37945585vyxu]

Hi Meenakshi,

thank you for the reply, i've now tried to replicate it using PDFs made with Adobe InDesign
but wasn't able to replicate the color error in Web UI that way.

When i used Adobe Acrobat to analyze the two example PDFs in this ticket i realized that there

are conflicting color values, e.g. a CMYK color value of 7.84/-2.0/-8.0, missing the Black value
and having two negative values. See the image.png i attatch to this message.

Means this ticket can be closed, the source of the error is a third party application having entered

nonsensical color values for PANTONE Black colors. And the reason why it didn't work in Web UI
but it worked in Acrobat is that Acrobat corrects those negative values, while Web UI takes them As-Is.

Best regards,

Sebastian