ExifTool Forum

[Originally posted by timflang on 2009-02-05 20:36:14-08]

Dear Phil

I recently noticed that when amending the exif times of photos they are not amending correctly. For example I have a photo whose exif time is 15:23:44, when the actual time is 15:23:05. However when I run exiftool it amend the time back by 39 seconds I get 15:23:22, which is 17 seconds away from what it should be. The larger amount of time that needs amending, the greater the gap of time. When I amend the filetimes using  a program called DTouch that amends the filetimees correctly.

I reinstalled my PC with Windows XP last July and upgraded to version 7.38 of exiftool. Today I tested version 7.65 and even the earlier version I had been using without problems before installing, 6.91, and all of them have the same problem. This has lead me to think the problem is being caused by my computer or new installation of Windows XP. However running a test using another program, Exifer, did not produce this problem. Has anyone else had a similar problem?

Regards

Tim

[Originally posted by timflang on 2009-02-05 20:40:51-08]

I forgot to include the command I'm using:

exiftool -AllDates-=0:00.39 -L -overwrite_original_in_place -P -r "to retime\2009-02-03" -k

[Originally posted by exiftool on 2009-02-05 23:31:47-08]

The answer is simple, and a bit funny actually.  Good thing you
gave your command line or I wouldn't have any idea what was
going on.  The command you used will adjust the time by 0.39
minutes.  You need to use a colon, not a decimal point.  Exiftool
accepts floating point values so you can do things like this:


The same thing works for minutes if you specify "hh:mm.mm" as
you did.

So you sould use "-alldates-=0:00:39".  I'm sure this will solve
the problem.

This is a case of exiftool being too flexible I guess.

- Phil

[Originally posted by timflang on 2009-02-06 09:48:27-08]

Phil

Interesting. Originally I used a : but at some point I switched to ., clearly a typo and I never noticed my mistake.

Thank you so much for resolving that problem. I just need to go back and find all the folders where the problem occurred. Not an impossible task as I have the file times to go on. It seems I was amending my photos by the equivalent of percentages of a minute instead of actual seconds.

Regards

Tim

[Originally posted by timflang on 2009-02-06 10:39:07-08]

Phil

Is there a tag for the file creation date? If there is then I could simply copy the file creation date and overwrite all the exif dates. I don't wish to use the file modification date since these can sometimes be a few seconds out. This would avoid having to work out which folders were wrong and the adjustments needed in time

Tim

[Originally posted by exiftool on 2009-02-06 11:18:00-08]

Hi Tim,

Some systems store a file creation date, but there is no built-in
Perl support for this date, so it isn't accessible from ExifTool.

- Phil