Exercise 4: Colour into tones in black and white

For this exercise I had to compose a still life image which included the colours red, yellow, green and blue. 

I then had to convert it to black and white in photoshop elements and adjust the colour filters to see what affect they had on the tones in black and white. 

Here are the results.

Neutral - as suggested by Photoshop

Red

Green

Blue

This exercise shows that adjusting the colour lightens the tone of that colour in the image and darkens the tone of the others.  This can be seen clearly in the above images.  It is also worth noting that the darkening effect is strongest on the complementary colour as can be seen in green above.  

I have to admit I never thought much about the effect colour had in black and white images.  I was therefore unaware how you could control the tone and bring out certain objects in the image by adjusting the colour levels.