Is there a direct way to change the 'created' meta data back to 'date taken'? My preferred cloud provider is sorting by 'date created', but sometimes i am re-editing images at some later time and would like to keep the original order of my images in the cloud, and therefore want to preserve the original time stamp. I can do it by using the meta data panel, but it would be more convenient to have some direct command. Ideally the code should be able to handle a bunch of files at once, like the panel does.
See near the top of this page: https://www.gpsoft.com.au/help/opus12/index.html#!Documents/Keywords_for_SetAttr_META.htm
Leo, i have edited my post. As it seems,
SetAttr META createdate:lastmodifieddate
does the job. I first have tried 'datetaken', but it gave me some year 1601 result. Thanks!
/e just a comment, the creation times are in some cases off by 1 second, but that's ok 
That might be the filesystem they're stored on. I think some still only have a time resolution of 2 seconds.
Edit: Although it's odd if the timestamp was copied from modified to created, as both are usually stored in the same way. So maybe it's not that.
It's not an issue. And wasn't there even a setting to use milliseconds? Anyway, if it's not a problem with syncing data or searching for doubles, the code is just fine.
Opus can show timestamps to the millisecond, yeah. (Whether the data from the filesystem is meaningful to those units can vary, but it should be on NTFS.)
Sync in Opus has an option to exclude seconds when comparing times, for this type of thing. Not sure that the Copy command has the same thing though, so it may depend how you're synching.
Would it be possible to share one of the files where using datetaken set the timestamp to 1901? I'd like to work out what's happening there, in case it's a bug and not just the data in the file. If there is one suitable for sharing, please zip it before attaching to a PM or reply, so the forum doesn't remove all the metadata. Of course, no problem if they can't be shared!
Yes, i remember that Millisecond setting and how to make Opus ignore it. I wonder who needs a ms precision, though. I will PM you one file. Note, that i only saw it happening with following command
SetAttr META lastmodifieddate:datetaken
I also wonder that. 
I think someone requested it; they must be doing something unusual.
Many thanks! I was able to reproduce the issue in 12.23, but also found it doesn't happen in our "future" branch of the code, so it should be fixed when that branch is released.
Cameras have been able to shoot more than one image per second for quite a while. Milliseconds are the logical step if a resolution better than one second is needed. So I'd rather wonder how long it will take until we reach microseconds