iPhone photos sometimes save the incorrect EXIF:OffsetTime* values

[Steerpike]

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At the very basic level, exiftool isn't that hard. Most of the time, you are either setting a tag to a value e.g. "-DateTimeOriginal=2024:10:13 12:00:00", or copying the value of one tag to another "-CreateDate<DateTimeOriginal".

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Just to give you the view from the trenches, your example here illustrates why it IS quite hard for a casual user .  First of all, you have '=' in the first example and "<" in the second (where '=' would be more intuitive).  Elsewhere, '<' is used for 'less than', and 'eq' is used for comparisons. Then there's the issue of some label references needing the '$' sign - I still haven't figured that part out . And why isn't '2024:10:13 12:00:00' wrapped in quotes, in your first example (rhetorical question!).

But it's extremely powerful and useful, and it has allowed me to clean up a real mess caused by an issue with my iPhone.  I'm sure it's as straight-forward as it can be, given all that it can do. Your assistance is greatly appreciated.

[StarGeek]

Then there's the issue of some label references needing the '$' sign - I still haven't figured that part out .

Anything that isn't a simple tag copy, e.g. "-TAGTarget<TAGSource", will probably need the dollar sign. For the most part, you can include it anyway, but there are a few obscure circumstances where it might change the results.

And why isn't '2024:10:13 12:00:00' wrapped in quotes, in your first example (rhetorical question!).

Except it is. The quotes just happen to also include -DateTimeOriginal=.

Quotes are something that is required by command line. They're needed to let the command line know that certain characters that the command line uses for special operations are part of the command and not to be processed.

Technically, all that would be needed would be quotes around the space
-DateTimeOriginal=2024:10:13" "12:00:00
But I find that confusing. If quotes are needed, I'll either put them around the entire thing, most commonly used with tag copies, or around the value to be set when it's a simple assignment.