Set the color temperature so objects on film actually look white.
All light resides on a color temperature scale, which is why different light sources have different colors (Kelvin scale)
Professionals will use a 18% gray card so that they have a consistent reference point to set exposure and white balance manually.
If you don’t have an 18% gray card you can use a white piece of paper to set white balance manually.
If the light coming from your subject is mostly blue, the camera will “compensate” by using a yellowish white balance and a reddish color profile.
You should set a custom white balance whenever the lighting changes.
Click the Q button to the right of the display
Select the AWB menu item on the left of the display
Select the last option (Custom)
Take photo of the 18% gray card
Click the "MENU" button the select the 3rd tab and "Custom White Balance"
The camera will find your most recent photo of the 18% gray card. Click "SET"
Click "OK"