Changing EXIF date on a NEF file does not work - should it? How do it?

[ubacher]

I have MWG set (default Imatch).
I suppose it is because of this that the Tool to change the EXIF date/time does not change the date/time in a NEF file.
Is there a way around it? Do I need to use EXIFTOOL for this?

PS: If the time change will/can not be made Imatch should inform me/refuse to let me use the tool.

[Mario]

Not enough info.

EXIF data is in the XMP file. And may also be in the NEF file if the NEF file contains EXIF data.

Do you allow IMatch to update EXIF data in NEF files?
Do you use embedded or sidecar files for XMP storage for NEF files?
If not, the EXIF data in the NEF will override the changes made by the tool on the XMP data.
Open the ExifTool output panel, do your update, and then attach the contents of the output panel. This will tell us what IMatch is writing, to which file etc.

[cytochrome]

It works here. I use "absolute mode" it works always. In "relative mode" I had some glitches (and I am not alone, I remember a recent post about this, can't find it back). But jI checked just and it worked.

I write to the NEF, and IPTC/Exif/ writing is allowed

Francis

[ubacher]

Do you allow IMatch to update EXIF data in NEF files?
Do you use embedded or sidecar files for XMP storage for NEF files?

I have not modified the settings Imatch comes with! I assume this means that NEF will not be allowed to be modified.
Exiftool output:
----------------------------------------------------------------------
-overwrite_original
-m
-use
MWG
-charset
ExifTool={PTETCHARSET}
-ex
-sep
,
-XMP:DateCreated+=0000:00:00 02:00:00

-XMP:CreateDate+=0000:00:00 02:00:00

-XMP:MetadataDate=now
-XMP:ModifyDate=now
D:\Foto Cache\2014-09-00 FALL\2014-09-20 SOLVEIG HOCHZEIT\2014-09-20_reg\20140920_0086.xmp
-execute
-execute9999

    1 image files updated
------------------------------------------------------------------------------
NEF file contains hour 9:32    (screenshot ExifTool output)
XMP file contains hour 10:32   (screenshot Exiftool output)

As can be seen the time in the XMP file was not changed.

To show that the IM EXIF time does not match what is returned by exiftool I show a screenshot
with both listings.


[attachment deleted by admin]

[joel23]

Do you allow IMatch to update EXIF data in NEF files?
Do you use embedded or sidecar files for XMP storage for NEF files?

I have not modified the settings Imatch comes with!

Works here too. The glitch Cytochrom refers to, was that this command didn't work when no XMP data already exists.
But of course you need to allow writing to Exif for NEF files.

I assume this means that NEF will not be allowed to be modified.

You can write what ever you want to NEF (A.Y.O.R.), IPTC, Exif and XMP. And sometimes we have to (once), because Exif and XMP better stays in sync - and MWG demands to sync them or to delete the value which can't be synced.

After you have enabled "write Exif", first launch a "force update" to sync your Metadata and check it again, 'cause IMHO you shouldn't even have the one hour difference for Exif:Time and XMP:Exif:Time. Can it be that XMP:Photoshop was changed as you expect it?
Just to make sure: there are no embedded XMP in the NEF?

[ubacher]

Since I tried various things while troubleshooting this I assume that some of the discrepancies were caused by this.
( I had also used EXIFTol GUI external to IM )   IM seems to use the photoshop date/time as the basis/master for the change.

Summary: I have to allow EXIF to be written for NEF files for the date/time change to work.
Since I like to stay with the default settings I return the setting to the default after the change.

A refinement for IM would be to allow EXIF writes for the case of date/time change (regardless of the settings) - or -
to warn that the date/time change can not be made with current settings.

Thanks

PS: Isn't it fun when you receive images from three different cameras and each has a time setting which is way off!

[Mario]

As you found out, IMatch is updating only the XMP record for your NEF file, but cannot synch back to EXIF because you don't allow this. When IMatch re-imports the metadata after the change, the MWG mapping EXIF->XMP re-imports the date and time stored in the NEF file itself and replaces the XMP timestamp.

A refinement for IM would be to allow EXIF writes for the case of date/time change (regardless of the settings) - or -
to warn that the date/time change can not be made with current settings.

It's not the date and time alone. I don't have the exact number available right now, but there are about a dozen EXIF tags which need to be synched with XMP and back. If you prevent IMatch from keeping EXIF/XMP/IPTC/GPS in synch, you will get problems.

[ubacher]

The default is to not let NEF files be updated. Once I changed the date/time there should be no need
for further writes to the NEF i.e. the default will work.

[joel23]

Since I tried various things while troubleshooting this I assume that some of the discrepancies were caused by this.
( I had also used EXIFTol GUI external to IM )   IM seems to use the photoshop date/time as the basis/master for the change.

For a quick and dirty DateTime shift you can use ET GUI (Modify -> Exif:DateTime shift) - it does not know about IMatchs' setting nor does it care when a file is r/o.
When the data is reloaded in IMatch, it syncs Exif to XMP. Means you don't have to switch settings and this prevents from forgetting to switch it back.
For other tags like GPS, Author/Artist, Copyright and Description etc. you better enable the writing in IMatch.

[Mario]

The ECP can also be used for that purpose.
Whatever you do, if the file also contains legacy IPTC data, make sure you also update the IPTC timestamps, and the IPTC digest information, or the XMP and the in-file data may get out of synch.