Shift EXIF Date and Time by an Offset in ExifToolGui

A camera clock that was wrong by two hours, or a timezone forgotten on a trip, leaves every timestamp wrong by exactly the same amount. Re-typing each date would destroy the real spacing between shots. The fix is a shift: move every DateTimeOriginal by one computed offset. ExifToolGui V6.3.12, Frank Bijnen’s maintained fork of Bogdan Hrastnik’s GUI for Phil Harvey’s ExifTool, exposes this in the Modify menu as the DateTime shift function.

Use this guide when the relative times are correct and only the absolute time is off. When a single file needs one exact new date, use changing DateTimeOriginal instead. Both live in the Tutorials hub, and the program is available from the download page.

Work Out the Offset From One Known Moment

A shift is only as good as the offset you feed it, so derive the offset from evidence. Find one moment you can time independently: a photo of a clock or departure board, a phone picture taken alongside the camera photo, or an event with a recorded start time. Compare that known time with the DateTimeOriginal the camera wrote for the same moment. The difference, hours, minutes and seconds, with its sign, is your offset.

Write the offset down before touching the software, including whether the camera was ahead or behind. A sign error doubles the problem instead of fixing it, and on a batch of hundreds of files that is an expensive mistake. As always with batch writes, test the shift on copied files first and read the results back before applying it to originals.

• Find one independently timed moment.
• Subtract the stored DateTimeOriginal from the true time.
• Note the offset and its direction (forward or back).

Run Modify, DateTime Shift on the Selection

Select every file that shares the same wrong clock in the file list. Files from a second camera with a correct clock must not be in the selection, because the shift applies to all selected files at once. Then open the Modify menu and choose the Exif/XMP DateTime shift entry. The V6 documentation describes this function as shifting all selected files by a computed amount, which is exactly the offset you derived.

Enter the offset carefully, double-checking the direction against your notes, and apply it. The GUI passes the operation to ExifTool, which rewrites the timestamps in place. A shift across midnight, a month end or a year end is handled as real date arithmetic, so a photo taken at 01:00 with a minus-three-hours shift correctly lands at 22:00 on the previous day.

Equalize EXIF and XMP After Shifting

Files may store capture time in both EXIF and XMP, and a library that reads the other copy will still look wrong if only one moved. The Modify menu’s DateTime equalize function aligns EXIF and XMP date-times, so run it on the same selection after the shift to bring both into agreement with the corrected value.

This pairing of shift then equalize is the standard tidy pattern for clock errors. It also matters before geotagging: matching photos to a GPS track log compares timestamps, so shifted, equalized times geotag far more reliably, as explained in geotagging photos from a GPX track log.

Verify the Shift on the Timeline

Verification is visual and quick. Sort the folder by capture date and check the known moment first: it should now show the true time you derived the offset from. Then check the first and last files of the set: both should have moved by the same offset, and the gaps between consecutive shots should be unchanged from before.

If the known moment is now off by twice the offset, the sign was reversed; shift back by the same amount to undo, then re-apply in the correct direction on your copies before touching originals. Once the timeline reads correctly, downstream tasks such as renaming by capture date and merging two cameras’ folders into one sequence will behave as expected.

Shifts, Timezones and Travel Sets

The most common real-world shift is the forgotten timezone: a camera left on home time through a trip abroad. The offset is the timezone difference for the destination, but check whether the trip crossed a daylight-saving boundary at either end, because a set spanning that boundary can contain two different true offsets. Split such a set by date and shift each part separately rather than forcing one number onto both.

Merged travel sets deserve the same care per camera. Derive each camera’s offset from its own known moment, shift each selection separately, and only then combine the folders. Verified separately, the two timelines land on the same true time; shifted together under one camera’s offset, the second camera’s photos would be wrong by the difference between the two errors, a subtler fault than the one you started with.

Frequently Asked Questions

When should I shift instead of setting a new date?
Shift when every file is wrong by the same amount, such as a wrong clock or timezone. Set an exact date when one file, or a set of scans, needs a specific timestamp regardless of the old value.

Does shifting preserve the order and spacing of photos?
Yes. Every timestamp moves by the same offset, so the intervals between shots and their chronological order stay exactly as they were.

Can a shift fix photos from two cameras with different errors?
Only one offset applies per run. Select each camera’s files separately and shift each set by its own derived offset so both timelines converge on the true time.

A correct shift restores a whole trip’s timeline in one operation. From here, the Tutorials hub leads on to geotagging the corrected photos, batch-editing their descriptive tags, and renaming them by their now-accurate dates.