white balance shift from camera to ACR/LR

[telmorrf]

Does any one knows why ACR/LR gives a different WB temp from the one that is setup on the camera?

Here is a list of the shift

          5D2          ACR

        2500K        2550K
        3000K        3000K
        3500K        3450K
        4000K        3850K
        4500K        4300K
          ...              ...
        5500K        5100K
        6500K        5900K
          ...              ...
        10000K      8300K

It happens with other canon cameras as well.

[Tyler Mallory]

Yep. It does this on my 1DsIII as well. Mine also displays a tint shift away from zero. I think ACR reads the metadata parameters you selected and then interpolates that into its own color recipe, displaying how its numbers jibe with the color temp number you selected in the camera. It's gotta read Canon's code, then spit out its own version of that, which looks like it may not be the same numbers.
At least, I think that's how that works...

[Panopeeper]

Does any one knows why ACR/LR gives a different WB temp from the one that is setup on the camera?

It sounds counter-intuitive, but the color temperature and tint are in the praxis not absolute numbers, because the illumination is not from an ideal black body. They are to be interpreted in relation to the correlated color temperature. Different raw converters may use different refernce points and calculate different temperature and tint, while yielding the same (or close) result.