Withou knowing any details, no one can guess.
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Firstly, I did perform a search before asking this question but didn't find anything, hence why I posted up a new question.
I am using latest Mountain Lion, using CS6, happy to answer any other questions needed to resolve this/
If you read the link I gave you, you'll know what kind of information is needed.
Things like exact version of Photoshop (not just "CS6" but something Photoshop like 13.0.5), exact version of Mountain Lion, machine specs, video card, how you are saving, etc.
Please read the whole link before posting again, including the part that explains that you are not addressing Adobe here but requesting help from other users, just like you, who are giving their time free of charge. No one is under any obligation to answer your question.
Photoshop Version: 13.0.5
OSX Version: 10.8.4
iMac: 27 Inch (Mid 2011) - 3.4Ghz i7 with 16GB Ram
I still do not know how you are saving, what your PDF settings are, etc.
All I can tell you is that what you are describing is in no way normal behavior, and I cannot reproduce your issue with the information I have before me—and I did try to reproduce it.
Basically a customer has sent us a PDF, it's the first time I have needed to open a PDF on CS6 (previously used CS4) and it opens inverted, when I open the same PDF in CS4 it opens as it should.
I haven't generated the PDF myself as it's one a customer sent so the settings seem irrelevant at this stage as I know the file opens correctly in CS4 it seems to be a version issue, just wondering if anyone has experienced similar instances?
Happy to upload the PDF in question to see if it can be replicated on other machines if needed.
I'll be happy to take a look at your file. Upload it to the FTP space of your choice, like Dropbox, yousendit.com, etc., and provide the link to it. If there are privacy or copyrights concerns, you can send a private message through the forum.
That file is damaged somehow. Perhaps during transport.
No other PDF file shows these anomalies on my machine, just yours.
• Double-clicking on it on the Desktop generates this error message:
• Control-Clicking on the Mac and selecting Open with Photoshop CS6, Photoshop 13.0.5 opens a 2500x1048 pixel image in inverted color mode just like you describe.
• Control-Clicking on the Mac and selecting Open with Acrobat Professional 8.3.1 opens an image with positive colors and the following properties:
• Control-Clicking on the Mac and selecting Open with Preview:
• Opening the image in the Dropbox on the web in the Firefox 23.0 web browser, opens up a positive color image, which when dragged to the Desktop generates a 2500 pixels by 1048 pixels JPEG file which Photoshop opens normally:
The Acrobat error message (first screen shot) may be a clue.
We (you and I) may have found a weird incompatibility of that file in Lion and in Mountain Lion.
I opened your file in any way imaginable on another Mac running Tiger 10.4.11, and the file opens without any problem by double-clicking on it on the Desktop in Acrobat. It also opens normally, with positive colors, in Photoshop 11.0.2, in Acrobat Professional 8.3.1 and in Apple's Preview.app.
Whatever damage the file suffered, it shows only in Lion and in Mountain Lion. That may give the Adobe engineers a clue if they read this.