Introduction
Problems with Colour perception and depth perception occur very frequently in our daily life and this seems to have rather comic or tragic consequences. We often hear arguments by drivers when they cross a red light at a signal with the driver saying it was green and the police insisting that it was orange or even red. The problem is that people have different perceptions about the colours and depth of objects. Part of the problem is created by our brain that assumes certain facts while actually, they are different. This paper discusses the colour and depth perception of objects that occur in everyday life.
Colour Perception
Colour perception is the ability of people to differentiate objects and things based on the colour or wavelengths of lights that they may emit or reflect. There are literally millions of variations in colours and the human eye can distinguish just a small percentage of these colours. Often what one sees and what one perceives are quite different and this can have comic consequences. Once when I was visiting my grandma in my native town, I realised the problems that colour perceptions were causing. My grandma had a cat that was dark grey in colour and I would feed it with milk and leftovers in the morning and during the night. I really could not distinguish the cat from another but it was only its colour through which I knew that this was the cat. After a couple of evenings, I realised that the cat was coming for its feed three or more times and mentioned it to my grandma who said ‘you are feeding the wrong cat’. I said that was not possible as the cat looked grey in the dark fading night and it answered my call of ‘Kitty’. To resolve this issue, I took a flashlight and when the cat came for the first time, I shone the flashlight on the cat and yes; it was our cat all right. After some time, when the cat came again meowing for milk, I shone the flashlight and to my amazement, I saw that it was much darker grey and almost black! The third time the cat came again, I saw under the flashlight, that it was pitch coal black!
What had happened was that my mind was ready to see a dark cat and in the faint light, I could not distinguish between different shades of dark colour and my brain had deceived me into accepting the cat as our own. There is a saying that ‘all cats appear grey in the dark. Given below is an illustration of colours perception and errors.
Depth Perception
Depth perception is the ability to see objects and scenery in three dimensions. With depth perception, we see distant objects as smaller while near ones are bigger. There is also the feature that as a person moves closer to the object, it becomes much bigger and there are different aspects that a person in a moving car will see nearer objects ‘move’ faster while distant objects ‘move’ slower.
The experiences with depth perception started when I was about five or six and my earliest memories are of sitting in the car while my dad drove. I was too young to notice the details but always observed that the trees and buildings seemed to rush by us while we remained steady and looking out of the car window, the road would zoom by till it was a blur. I also observed that trees appeared small when they were at a distance and as we approached them, they would increase in size till they filled the entire window. I would often wonder what was happening and never got a satisfactory answer. This was actually depth perception at work. My grandma’s house could be seen from a hill and appeared small and as we approached it, first the trees would look bigger and bigger and then finally her house would appear as if rushing at us. I would often ask why the house came at us so slowly while the trees came up so fast.
References
eChalk, 2009. eChalk Optical and colour illusion and perceptions. Web.
MSN, 2009. Dept Perception. Web.