trying to update WB tag for Canon R5 .CR3 file

[ETUser]

Hi

I am trying to update WB tag for Canon R5 .CR3 file

Tag is WB_RGGBLevelsAuto

It is writeable according to what I read in Exiftool @ https://exiftool.org/TagNames/Canon.html

Here is what I use in command line (Windows) and output

Z:\>exiftool -WB_RGGBLevelsAuto="1086 1024 1024 1213" 020A0088.CR3
0 image files updated                                                                                                                                                                           
1 image files unchanged

Why not updating ?

[Phil Harvey]

Unfortunately this tag is stored in the timed metadata of the CR3 file.  This is essentially a separate track in a video file (CR3 is based on the MOV/MP4 video format), and ExifTool does not yet have the ability to edit timed metadata.

You can use the -G5 option when extracting to see the gory details about where tags are stored.  Static Canon tags may be edited (ones found in MOV-Movie-UUID-Canon-MakerNoteCanon), but the timed ones may not (in MOV-Movie-Track-Media-MediaInfo-CTMD-XXX-MakerNoteCanon).  (My guess is that CTMD stands for Canon Timed MetaData.)

This is different from CR2 files which are based on the TIFF format and are much simpler because there is no timed metadata.  For these, all Canon tags are writable, which is why it shows up as writable in the documentation.

- Phil

[ETUser]

Thank you

well I can convert .CR3 to DNG, get WB tags out from CR3 and write them in DNG - now how 'd convert 4 int WB values from .CR3 into 3 float numbers for DNG staying in command line w/o going into much scripting 

PS: actually just 2 int into 2 float... with "G" I can simply write constant 1.0

[Phil Harvey]

I'm guessing that you could use the ExifTool Composite RedBalance and BlueBalance tags for the red and blue in the DNG.  These are just R/G and B/G from the WB_RGGB values.

- Phil