In the previous (Bokeh) experiment I had the camera on Auto White Balance. Although the lighting color temperature in my basement studio did not change, the variation of distance to the subject and the amount of Christmas lights in the viewfinder was sufficient to alter the white balance significantly.
After producing these JPG images I tried to lookup the actual colour temperature of each, but found that Adobe Photoshop, as well as Lightroom do not give colour temperature in deg. K but only an “As Shot” indication with the slider centered. This allows for only relative white balance adjustment rather than exact colour temperature settings. I then tried the “Camera Raw” filter in Photoshop. This also gives only relative colour temperature for JPG files.
To get an exact colour temperature I had to open the RAW file in Photoshop. You also get the exact colour temperature when you open a RAW file in Lightroom. Only then was I able to adjust each image to an “exact” colour temperature
The prudent thing to do before the shoot is to fix the white balance in-camera, rather than going back to alter colour temperature during post processing.
