PhaseOne P 65+ User Manual page 42

All subsequent captures will now have the new custom white balance
applied.
3 different custom white balances can be defined and used as shooting
white balances.
Custom white balance from Capture One
You can also choose to easily transfer a white balance from Capture
One to the P+ back:
1. Create a custom white balance inside Capture One.
2. While tethered to the computer select WB from the lower right button
on the P+ back.
3. Select "Custom1", "Custom2" or "Custom3" on the P+ back
depending on where you want to store the new white balance. now the
back is ready to receive the WBinfo from Capture One 4
4. Finally Click the "Set as capture white balance" button inside Capture
One.
5. Now the selected custom WB will be shown
P 65+ will beep, confirming that the custom white balance is now
uploaded, will be applied when the P+ back has been disconnected.
This technique is useful because you can bring up to three predefined
custom white balances taken in the studio to your location shoot.
Please be aware that when shooting tethered to the computer, the white
balance must still be set in the Capture One application. White balance
cannot be set on the P+ back while tethered.
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