How Humans See Colour

[Mike Farley]

There is an interesting article on LuLa which goes into the science of human colour vision.

http://www.luminous-landscape.com/essay ... lies.shtml

The bottom line is that around 10% of the human population experience colour in a way which deviates from the majority. Based on my own experience when I talk about colour vision in my presentation on composition, camera club members tend to be a self selecting group. Around 8% of the male population has the most common form of colour blindness, the inability to distinguish between red and green. Yet it is very unusual to find people at clubs who are colour blind and the overall percentage is far lower than average.

The article does address the importance for designers to take vision defects into account and claims that this should also apply to photographers. What it does not state is how many of those who cannot perceive a full range of colours take an active interest in those visual arts where colour has a significant role. While it has to be a concern for those producing commercial output, for example product illustration, I suspect that for most photographers it need not be a consideration.

[Rose]

My husband is red/black colour blind (as well as red/green). This is not all that uncommon, and it affects him pretty much every day. Manufacturers persist in making battery chargers in black or dark grey plastic, with red , orange or green lights... All of which are indistinguishable if you're colour blind. Bob never has a clue whether his phone, or camera, or tablet, or Kindle etc is charged or not, and he always has to ask me to check. The best chargers flash at different rates to indicate the level of charge and then the light stays on when full, so regardless of the colour, you can tell immediately when something is charged or not. Why can't they all be like this ?!!

[Mike Farley]

My husband is red/black colour blind (as well as red/green). This is not all that uncommon, and it affects him pretty much every day. Manufacturers persist in making battery chargers in black or dark grey plastic, with red , orange or green lights... All of which are indistinguishable if you're colour blind. Bob never has a clue whether his phone, or camera, or tablet, or Kindle etc is charged or not, and he always has to ask me to check. The best chargers flash at different rates to indicate the level of charge and then the light stays on when full, so regardless of the colour, you can tell immediately when something is charged or not. Why can't they all be like this ?!!

I must admit that until I read the LuLa article, I had not considered the impact of colour blindness on design. Clearly the message has not got through to some designers, either. I have a slightly different problem as on some battery chargers the light stays illuminated until charging is complete when it goes out, while on others it stays on. I cannot always remember which is which.

Earlier this year when visiting another club, one of the members there told me about a friend of his who had been driving London tube trains for 25 years without incident. During a routine medical exam it was discovered that he was red/green colour blind and had been relying on the position of the illuminated signal to determine whether he could proceed. Unsurprisingly, he did not drive again and Transport for London dismissed him shortly afterwards. What is more remarkable is how his vision defect had remained undetected for so long.

One question I have for those colour blind photographers I meet is about their coping strategy. Some shoot in monochrome, while others either know that certain objects such as London buses and pillar boxes are red and compose accordingly or seek input from their wives when they are unsure.

[Rose]

Monochrome wouldn't help in many cases of colour blindness. For example - Bob can't see red berries on trees, not just because he can't distinguish red from green but also because he sees no difference in the contrast, so it all merges until he's close enough to see outlines.

[Mike Farley]

Gosh, shooting monochrome when colour blind is trickier than I thought. I can see that it would certainly make genres such as plant photography much more difficult.