Different modifydate value (PDF tag) between ExifToolGUI and exiftool script

[joymac]

Hi to everyone and thank you to Phil for this fantastic script!
I got a problem in a pdf file. Is an important information because I'm using that for forensic reason.
Using ExifToolGUI on a Windows PC, I got for the modifydate PDF Tag this value: 2018:09:04 13:09:05+02:00.
But if I use the script directly on my mac I got this value: 2018:09:04 09:52:08+02:00
As you can see the date is different not only in hour but also in minutes and seconds.
Why?
The first value (the one i got with GUI) is interesting, because the pdf was changed (probably with imap) in a man-in-the-middle fraud.
The original modifydate of the original pdf file is 2018:09:04 09:52:08+02:00, in both GUI and script.
The file with the 13:09:05 date time is the modified one (below the pdf tag sections for both files).
Thank you to everyone who could help me in this situation.



Original:
---- PDF ----
PDF Version                     : 1.5
Linearized                      : Yes
Create Date                     : 2018:09:04 09:51:18+02:00
Modify Date                     : 2018:09:04 09:52:08+02:00
Producer                        : doPDF Ver 8.6 Build 942
Page Count                      : 1

Modified
---- PDF ----
PDF Version                     : 1.5
Linearized                      : No
Page Count                      : 1
Modify Date                     : 2018:09:04 13:09:05+02:00
Create Date                     : 2018:09:04 09:51:18+02:00
Producer                        : doPDF Ver 8.6 Build 942

[Phil Harvey]

If you are using the same version of ExifTool on both the Mac and PC it should give the same results.

What is your exact command?  You should be using the -a option in case there are duplicate tags.

If you get a different output from the same ExifTool version and same command for Windows and Mac, I would like to see the PDF file if possible (email me: philharvey66 at gmail.com).  I'll erase it after I analyze it.

- Phil