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There's no zone information in the capture timestamp. Why?

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    \$\begingroup\$ Possible duplicate of Is there any hope for Exif TimeZoneOffset as a standard? \$\endgroup\$
    – StephenG - Help Ukraine
    Commented Feb 18, 2018 at 18:48
  • \$\begingroup\$ Similar topic, but not really a dupe IMO. \$\endgroup\$
    – Caleb
    Commented Feb 19, 2018 at 5:49
  • \$\begingroup\$ different if only because the OP asked "why?" Granted that makes it kind of unanswerable... \$\endgroup\$
    – PhotoScientist
    Commented Feb 19, 2018 at 14:11
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    \$\begingroup\$ Why? Because Exif designers didn't see beyond their nose. \$\endgroup\$
    – Déjà vu
    Commented Mar 4, 2022 at 10:24

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CIPA DC- 008 is the standard for Exif 2.2. Of note it makes no mention of "timezone." "GMT" is also not mentioned either. The term "UTC" does appear but only specifies the GPS time is recorded as such. Pedants may note that this is slightly misleading since GPS time is not identical to UTC

My point, in short, is that omission of timezone is likely not accidental. I'm not saying that CIPA or JEITA thought it was a good idea to leave timezone out. I have no way of knowing how they felt about the decision. The fact that UTC is specified in one time tag and not in another means that the creators of the standard were aware they were leaving it out.

I can't say for sure but I am willing to speculate that usually when something is ambiguous in a standard it is because of a disagreement in the committee that created it. I suspect that unless somebody unearths the transcript of the discussions around creation of EXIF we will never really know why.

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EXIF v2.31 (p49) defined time-zone offset fields in 2016 and the XMP time-zone guidelines (p33-34) also consider time-zones. The implementation in cameras and programs is rather minimalist at the moment.

See also my answer to an older question: What do you do with your camera clock time in relation to time zones?

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    \$\begingroup\$ I upvoted this answer because it cites what sound like fairly authoritative articles, but, unfortunately, the XMP timezone guidelines link is currently broken. \$\endgroup\$
    – Michael Scheper
    Commented Jun 23, 2019 at 10:18
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    \$\begingroup\$ @MichaelScheper, seems like the whole website of MWG is down. Hard to find out what happened to them. Metadata anarchy, here we come... \$\endgroup\$
    – aXeL-HH
    Commented Feb 28, 2020 at 11:22
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    \$\begingroup\$ I've updated the link to EXIF v2.31 (pending approval). This should be the selected answer these days, given that new cameras are actively using the new time zone fields. \$\endgroup\$
    – lxgr
    Commented Apr 8, 2020 at 7:55
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    \$\begingroup\$ wayback machine archive of the MWG doc: web.archive.org/web/20180919181934/http://… \$\endgroup\$
    – blalor
    Commented Jun 26, 2020 at 10:27
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    \$\begingroup\$ Indeed, at least recent Android camera apps do provide time zone information (which usually has been automatically obtained by the device from the mobile network). The Google Pixel Camera, as well as the Android stock camera, sets all of OffsetTime, OffsetTimeOriginal, and OffsetTimeDigitized, while the Samsung camera does not set OffsetTimeDigitized. \$\endgroup\$
    – dvo
    Commented Aug 29 at 18:50
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Look at a Time Zone map. Time Zones are local political decisions, not necessarily agreeing with simple 15 degree longitude lines. For GPS to get it correct, the camera would have to have extensive lists including everywhere time zone did not map to longitude. Our computers and our cameras can't know this, and don't try to deal with that, they simply ask which time zone we want to show.

Knowing GMT is a lot to know, but we can set our camera to show whatever time zone we wish.

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    \$\begingroup\$ The OP didn't ask why the camera doesn't determine time zone from GPS data, they asked why the time zone isn't recorded in the EXIF data. Many cameras let the user enter time zone along with the date and time; including that information in the EXIF info would presumably be pretty simple. \$\endgroup\$
    – Caleb
    Commented Feb 19, 2018 at 5:39
  • \$\begingroup\$ Time Zone is Not an observable feature, a difficulty of course assumed to apply to GPS satellites too. :) \$\endgroup\$
    – WayneF
    Commented Feb 19, 2018 at 14:51
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    \$\begingroup\$ It's exactly as observable as Artist and Copyright, two other values that the user sets. \$\endgroup\$
    – Caleb
    Commented Feb 19, 2018 at 15:46
  • \$\begingroup\$ Exactly, that was my point too. The user can set whatever Time Zone they want to see, but it is not otherwise detectable by external direct observation. That's what makes it difficult to add to Exif too. Yes, I did err in assuming GPS timestamp, since of course we do know our own Time Zone, but Time Zone can confuse it when traveling. \$\endgroup\$
    – WayneF
    Commented Feb 19, 2018 at 16:54
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    \$\begingroup\$ Actually, it seems that Google Photo, and sometimes Facebook, tries to infer timezones from geodata, and assumes that the EXIF time is in that timezone. That's my best guess for why it seems to mess up the timestamps so badly, anyhow, since I try to keep EXIF timestamps UTC. \$\endgroup\$
    – Michael Scheper
    Commented Jun 23, 2019 at 10:21

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