Exercise: Control the strength of a colour.

This exercise aims to show how a colour appears to change as the exposure is changed. Several images were taken of the same painted metal door; the shutter speed was held at 1/80 sec (and ISO at 400)  but the aperture - having initially been automatically set by he camera at f4, was manually opened up and then stopped down to produce a range of images from over-exposed to underexposed. Overall the 5 images cover 2 stops

f2.8

This image is over-exposed by one stop and the blue is quite pale and washed out. The image could be described as light.

f3.5

This image is over-exposed by 1/3 of a stop.

f4

This was the exposure initially set by the camera.

f5

This image is under exposed by2/3 of a stop

f5.6

This image is underexposed by one stop and the blue is clearly much darker and more saturated looking than the original, and certainly very different to the image which is 2 stops lighter. 

It is clear when scanning through the images that as the exposure is reduced, the blue colour of the door becomes deeper and richer. The hue remains the same - it is blue - but the brightness and saturation change.