CanonVRD: WBAdjRGBLevels or WBAdjRGGBLevels?

[ewg]

Hello!

The tag that changes it's 3 values when one uses 'Click white ballance' tool within Canon's DPP is called 'WBAdjRGBLevels' (ExifTool 8.56 + GUI 4.11). It's strange the first two (out of 3, RGB?) values are always identical - they change much like two Gs in an RGGB color matrix. The value that usually differs is the last/3rd one (B?). Seems to me, one more (first R?) value is missing here... I suppose the tag (given its present 3-value behaviour) actually should consist of 4 rather than just 3 values - quite like all other WB tags in the CanonVRD section. All of them take 4 (RGGB) rather than just 3 (RGB) values...  

Would it be possible to somehow recheck this particular tag of Canon's exif structure, because now it makes no sense? This is probably the crucial point in deciphering how actually DPP 'Click white balance' tool works (no info in DPP at all).

In other words - WBAdjRGBLevels or WBAdjRGGBLevels?  

Any other ideas?

[Phil Harvey]

You're right, there is something wrong with this tag (DPP 3.9.2).  I'll look into this to check to see if it depends on DPP version.

Edit: I think you're right that for this version of DPP the tag is actually extracting the GGB levels, and the R level is missing.  Thanks for pointing this out.  I'll fix this in the next release, but I still need to check this against older versions of DPP.

P.S. I like your use of colour, but what about WBAdjRGGBLevels ?

[ewg]

P.S. I like your use of colour, but what about WBAdjRGGBLevels ?

That's exactly what I meant!  

Thank you for Your insight into this. - I'm honoured!  (ExifTool - good job!)

[ewg]

ExifTool 8.59 - Thank you!