What makes a colour?

Exercise: Control the strength of a colour (5 Photographs)

There are several techniques to give you control over a colour in a photograph at the time of shooting. One of the most basic is over saturation. 

This exercise calls for a series of images to show how colour changes with exposure, as under exposure produces a stronger colour while over exposure produces a weaker colour. 

In the series of photographs below, I varied the aperture by 1/2 stop each time to see what effect this had on the original colour. 

I wanted to photograph pure red, as I thought this was the best colour to demonstrate the effect of different exposure. Where do you find red doors? the fire station of course!

All of these images were taken at Bude Fire Station on an overcast afternoon in March. 

The RGB figures for each image were taken from Lightroom and are displayed under each image. 

Image 1

R- 91.2 G- 22 B- 27

Image 1 was taken at 1/125sec @ f4. This was the cameras metered setting for this image to be correctly exposed. 

Image 2

R- 85.4 G- 2.7 B- 21.5

Image 2 was taken at 1/2 stop under exposed, 1/125sec @ f4.5

Image 3

R- 79 G - 0 B- 16.3

Image 3 was taken at 1 stop under exposed, 1/125sec @ f5

Image 4

R- 91.2 G- 22 B- 27

Image 4 was taken at 1/2 stop over exposed, 1/125sec @ f3.5

Image 5

R- 100 G- 28.1 B- 30

Image 5 was taken at 1 stop over exposed, 1/125sec @ f3.2

As you can see from the sequence of photographs above, the actual colour changes with exposure, images 2 & 3 produce a stronger colour as these images are under exposed and in images 4 & 5 the over exposure creates a weaker colour. 

The RGB values for each image show that as the exposure decreases the red value decreases, and conversely as the exposure increases so does the red value.