Does Time Wiz clear sub-second times in EXIF?

[PandDLong]

My photos when loaded will have EXIF sub-second times (Original & Digitized) - these show in the iMatch Metadata Browser.

When adding time zone data (through Time Wiz),these are now showing as blank.

Is that the intended outcome or am I misusing something?

Michael

[Mario]

The TimeWiz does not touch XMP other than date created / date subject created.
Do these XMP tags contain subseconds before? How do you change them, which options do you use? Where can I download a sample file you have used?

[PandDLong]

Okay.  I will do a little more testing with structured scenarios and send you the info.

Michael

[PandDLong]

Here are two photos (the second is in the next post due to size limits).  The copy was made prior to putting both files into a folder that IMatch has indexed.  I do not apply any metadata changes or templates on indexing.

The 'Eiffel' file is as generated by the camera.  It shows subsecond times in the EXIF data in the browser.   (I note that the XMP-Exif record in the browser did not show these values but I assume that is because they are not tags listed in the IMatch tag selector).

The 'Eiffel - Copy' had two changes.  I wrote a title then I used Time Wiz to set the time zone to +02:00 and shift the time by substracting 2 hours.  (I have included a screen shot of this as it shows the subsecond time as part of the "original value").

After running Time Wiz, the sub-second times still showed in the browser.  No other metadata changes were done.

After completing the write-back the subsecond times disappeared from the browser (and a panel which explicitly references the tags shows them as blank).

For me this is not critical, it was just unexpected behavior.  I noticed that some people use subsecond times in file naming and in some photo shoot scenarios, I would think it is an important field.

Let me know if you would like any additional information.

Michael

[PandDLong]

Second post with modified photo and screen shot of Time Wiz.

[Mario]

Always ZIP image attachments. The community software re-encodes every image and this may cause metadata to be lost.

Looks like the time manipulation library trims the sub-seconds while shifting.
Not sure if sub-seconds are so important, especially not for apparently scenic photography. High-speed or sports may be something different, but pro's usually keep their clocks on UTC anyway

I shall look into this glitch for IMatch 2021.

[PandDLong]

Sounds good.

You are right - subseconds are not important to me (especially for scenic photos).

Thanks for the tip to zip attachments (hopefully I remember...).

[PandDLong]

A couple of final findings and thoughts on this topic.

1. If one goes to manually edit the Date fields (the XMP and/or XMP Photoshop tags) - the subseconds appears in the tag field appended to the time - like it shows in TimeWiz.  Making a change then deletes the SubSec time from the EXIF same as TimeWiz. Further support that this is a time manipulation issue.

2. I also dabble in some wildlife photography and this data may become important in that case.  I say may as I haven't catalogued any of those photo sets yet. However, I can copy the SubSec tag info to a safe place and reference it if I need to keep track of photo chronology within the same second.   (I don't believe I can copy that info back to the "correct" metadata tags as SubSec is not a supported iMatch tag and thus no access to edit or have as a template target).

3. Camera on UTC is sounding like a good idea - doesn't solve any of the historical images but may make it simpler in the future.  (It is ironic as one of the top things many amateur/hobbyist web sites promote is to always set your camera to local date/time - one of those things that divide the amateurs from the pros).


I look forward to iMatch 2021, you have put a few hints of things you are working on.

Michael

[Mario]

The TimeWiz did not check for and parse sub-seconds contained in the source timestamp (in the format .sss).
I have extended the TimWiz for IMatch 2021 to detect milliseconds in the source timestamp and to retain them when shifting date and time or manipulating the time zone.
When a variable or absolute timestamp is used, and it contain milliseconds, IMatch applies the milliseconds to the resulting timestamp.