ExifTool Forum

ExifTool => Newbies => Topic started by: Fi156 on June 26, 2016, 05:39:30 AM

Title: [Geotagging] How to bypass the timezone logic?
Post by: Fi156 on June 26, 2016, 05:39:30 AM
Hello guys,

everytime I use the geotagging option in Exiftool I am having huge problems with different timezones.

My usecase is very simple:
I have a photo which shows the actual UTC Time. >> GPStime
And I have another time in the exif tag. >> PhotoTime

Next I substract the PhotoTime from the GPStime. >> SubstractedTime

When I now use Exiftool with the following parameters:
exiftool -geotag GPXFileLoc -geosync=SubstractedTime -'geotime<ModifyDate' *.jpg

I will end up with a wrong result. I assume, that exiftool will always try to apply some Timezone shifting to my input.

How can I prevent this behaviour?

Regards, Simon
Title: Re: [Geotagging] How to bypass the timezone logic?
Post by: Phil Harvey on June 26, 2016, 07:01:40 AM
Hi Simon,

ExifTool assumes the local time zone unless the GeoTime you write contains a time zone.  In your case you are writing ModifyDate, which won't have a time zone.  If it is UTC, then you need to do this: '-geotime<${ModifyDate}+00:00'.  This is just like example number 6 on the Geotagging page (https://exiftool.org/geotag.html#Examples).

- Phil
Title: Re: [Geotagging] How to bypass the timezone logic?
Post by: Fi156 on June 27, 2016, 04:18:14 PM
Hello Phil,

thank you!
It works now.

(I looked into the examples beforehand, but was not able to related that to my problem - sorry!)

Keep up the great work :)
Regards, Simon