The second part of the exercise asks you to repeat the exercise (i.e. using a full sun, shade and late light) but in doing so vary the white balance setting using daylight, shade and auto settings.
The logical think would have been, I suppose to use the same subject for all nine shots but this option was not practical so I used different subjects for the three scenarios.
For the Sunlight one I used my sister’s dog basking in the sun in our lounge:-
Interestingly, according to lightroom the colour temperature settings for Auto and Daylight were very close (4900 and 5000 respectively) while shade was 7200.
For the shade shot I used our coalbunker at the bottom of the garden I left the blue net on it as I thought it would be interesting to see what happened to that.
Again the auto and sunlight are similar, well more than similar in this case as the colour temperature for both is 5000, the equivalent value for the shade version being 7200 again as might be expected. Both the auto and daylight versions give a colder version of the real thing (with the daylight bringing in a tinge of green in the concrete). The shade version, as you hopefully expect, is the most accurate rendition.
In this case the colour temperature of the auto shot at 5200 was slightly higher that the daylight 5000 and shade was obviously 7200 again. Note how the shade version darkens (to my eyes almost adding a hint of brown) the sky and the whites(?) of the building. Of the three I think the auto is the best rendition and in some ways you would expect this to be the case as the shot was not true sunlight nor shade so those two settings were always going to misrepresent the scene to a greater or lesser degree.
As I shoot in raw I don’t use the white balance much as I can alter it if necessary in post processing and, in any event, auto white balance is usually pretty good for most situations.
Out of interest I applied the Lightroom presets for daylight and shade to the auto shot of the buildings and these are the respective results:-
For daylight Lightroom uses a colour temp of 5500 slightly above that of the camera and likewise the shade temperature setting is 7500 so not too far out but enough to make a difference. This variation will have to be kept in mind.