ExifTool Forum

General => Metadata => Topic started by: calestyo on May 30, 2011, 10:39:02 PM

Title: where does EXIF:TimeZoneOffset (0x882a) come from
Post by: calestyo on May 30, 2011, 10:39:02 PM
Hi.

Exiftool seems to support a tag TimeZoneOffset (0x882a).

Where does this come from?

Even in the most recent version (2.3) of the Exif standard this is not mentioned.


Cheers,
Chris.
Title: Re: where does EXIF:TimeZoneOffset (0x882a) come from
Post by: Phil Harvey on May 31, 2011, 07:06:32 AM
Hi Chris,

Only the underlined tags in the EXIF tag name documentation (https://exiftool.org/TagNames/EXIF.html) are part of the EXIF standard.

The tag you mention is documented here:

http://www.broomscloset.com/closet/photo/exif/TAG2000-22_DIS12234-2.PDF

See the Image::ExifTool::Exif source code (http://cpansearch.perl.org/src/EXIFTOOL/Image-ExifTool-8.50/lib/Image/ExifTool/Exif.pm) for all my references.

- Phil
Title: Re: where does EXIF:TimeZoneOffset (0x882a) come from
Post by: calestyo on May 31, 2011, 08:57:23 AM
Hi Phil.

Thanks for the hint.

So this is an "official" tag via the TIFF/EP standard? Or is it just something that was mapped from TIFF/EP into exif.

Can it be actually used to give the Exif Date/time fields an unambiguous meaning?
What would I e.g. set, if I configure my camera to use UTC?


Thanks,
Chris.
Title: Re: where does EXIF:TimeZoneOffset (0x882a) come from
Post by: Phil Harvey on May 31, 2011, 09:26:29 AM
Hi Chris,

Non-standard EXIF tags may be used for your own purposes, but don't expect other software to honour them.

- Phil
Title: Re: where does EXIF:TimeZoneOffset (0x882a) come from
Post by: calestyo on May 31, 2011, 09:36:47 AM
So this basically means I cannot really use any of the nun-underlined tags... :-(