Exercise 27: Colours Into Tone in Black and White

This is the most confusing exercise so far. The instruction is simple, but I have no idea on what is the purpose of this exercise. If you have to deploy colour filter, this is effectively set the brightness of the other colours to zero. As a result, these colours will appear dark in the black and white image. 


Anyway, for the sake of simplicity, I took a snapshot of my  bookshelf. This is  what it is like. It is very boring, but it has all the colours the exercise asked for.

 

Now, turn this into black and white as is:

 

Now with the Blue filter. Somehow Goldstein's Classical Mechanics survived even though it appears to be green in the original (colour) image. So this green is not as pure as the Macroeconomics book next to it.

Now the green filter:

 Red filter:

Yellow filter: