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Interesting Antique Optical Illusions and Facts about Illusions
Recently, I came upon these old postcards and wanted to share them. They evoke a long gone era and interesting subject matter. They are optical illusions. I have seen one of them fairly often ( the woman at the mirror) the other two, I have never seen before.
Optical illusion is fun.
Blame the science of how our eyes function and the fact we are programmed to interpret or rather misinterpret what we see!
Magicians and artists have used optical illusion in their crafts for ages. Our eyes play a part between objective reality and visual perception and it has everything to do with how the eye functions and how our brain processes the information.
Our eyes perceive through electromagnetic waves called light. Sight is a sensation of light! Because of that our vision is something that is experienced internally (ie. in the brain). Seeing is considered a subjective experience and that is why misinformation happens!
Optical illusions fool our eyes making us think we are seeing one thing using the information of how we see to fool us.
Look at the postcards as you normally would. Then look at them with your eyes out of focus..a new picture emerges!
How Does an Optical Illusion Happen?
We See With Our Brain
The eyes are our "camera", however, seeing, happens in our brain. Our brain processes the data the eyes send it. The brain stores experiences in memory and this affects what we see because the brain will interpret automatically and we can not switch off our brains!
What we believe, incredibly, also affects our vision. Part of this has to do with focus, attention and being too "attached" to certain outcomes. Our beliefs can be counter productive to seeing accurately. Call it "selective vision".
Our area of focus is small, so if we focus on a beautiful flower, for instance, we may miss the skunk five feet away from us (unless it moves)! The same goes for attention; much could be going on in our field of vision but if we are not attentive to it, obviously we have not seen it. Same goes for attachment. If we are looking at something, say a leaf, we may not see the bug on it since it also looks like a leaf! We are expecting a leaf.
Rods and Cones
Rods and Cones
The eye has two kinds of features that are responsible for everything we see.
These are our high-resolution vision receptors. They are contained in a small area of the eye. Cones give us our sense of colour. With the cones we can see all the colours in the spectrum of sunlight. We use our cones to read and drive and for anything that requires us to focus in on tiny details.
Rods comprise a much larger area of our eyes. They provide us with the "big picture" in any scene. The rods pick up movement and shapes. We get information about our environment from our rods! The rods are colour blind and are better in the blue shifted light of twilight and night. They are low-resolution sight.
The rods and cones work together. The rods pick up movement and alert us to focus the high-resolution cones to get a better picture.
Other trivia on sight
- Our eyes are able to see brightness, contrast and movement.
- Our eyes see colour, but only in a very small area of the entire eye.
- Movement, shapes and change are more easily picked up in our peripheral vision
- We tend to catch rapid as well as large movement/changes.
- Tiny and subtle changes are much harder for us to detect.
- Changing lighting can fool the eye; while the colour changes with the available light the eye only perceives the one colour, not the variations during the day.
- The eyes notice areas of greatest contrast and the clearest view and ignore subtle nuances.
- One colour that is exactly the same shade and hue will appear to the eye as a shade darker or lighter by using any other colour behind it as a contrast. This is used in decorating and by artists.
- Light coloured objects appear larger than darker objects even though they are exactly the same. (hint for those who want to appear slimmer :) ) What we perceive is not always what actually is.
- Some colours appear to advance, while others recede.
Common Optical Illusions
- The moon appears much larger on the horizon than when it is further up in the sky
- A mirage is the appearance of water on the horizon where there is none.
- A straight road narrows as the distance increases until it disappears at the horizon point.
- ·Nature is full of trickery, especially in the insect world.