Nikon Z 7 Reference Manual page 88

D
White Balance Fine-Tuning
At settings other than Choose color temperature, white balance can
be fine-tuned using the White balance items in the i menu and the
photo and movie shooting menus (0 97).
A
Color Temperature
The perceived color of a light source varies with the viewer and other
conditions. Color temperature is an objective measure of the color of a
light source, defined with reference to the temperature to which an
object would have to be heated to radiate light in the same
wavelengths. While light sources with a color temperature in the
neighborhood of 5000–5500 K appear white, light sources with a lower
color temperature, such as incandescent light bulbs, appear slightly
yellow or red. Light sources with a higher color temperature appear
tinged with blue.
"Warmer" (redder) colors
3000
In general, choose lower values if your pictures have a red cast or to
intentionally make colors colder, higher values if your pictures are
tinged blue or to intentionally make colors warmer.
64 Basic Settings
4000 5000
"Cooler" (bluer) colors
6000 8000 10000 [ K ]