Turn your photos into 3D pictures

The biggest new technology this year, whether at the cinema or in the television aisle of high-street electrical retailers, must be 3D pictures. It’s an exciting technology and, although you might think that this kind of effect is the preserve of huge movie studios, it’s surprisingly easy to make your own 3D images at home.

Various companies are now making 3D cameras, but in fact you don’t need to buy any new equipment at all. In this issue we will explain how to make 3D images using any standard digital camera, or even cameraphone, and some free software.

You will need to buy some red/blue anaglyph glasses. These can be bought very cheaply with cardboard frames, but we would recommend paying a little more if you decide to do more work in 3D. The results will be better if you have money to spend on more expensive 3D monitors and glasses, but red/blue glasses can give surprisingly good results.

How does 3D work?
We see the world in three dimensions because we have two eyes that see slightly different images. Our brain then interprets the differences between what the eyes see to work out the distance to an object.

This all happens without us being aware of it, but you can get a sense of the difference by closing one eye and then the other. What you see appears to move left and right. This concept was used on battleships to estimate the range to targets before the advent of radar.

Our eyes are level but about 9cm apart horizontally. To record a 3D image with a camera or camcorder we need that device to also take two pictures from points a small distance apart – and, as we will explain later, although it is simplest to take the two images simultaneously, it is also possible to snap these pictures one at a time.

Making 3D work onscreen
Having recorded a 3D image we need to display it. 3D displays do this by using various methods of delivering a different image to each eye. Old-fashioned ‘magic eye’ images did this by forcing people to unfocus their eyes in order to see the image, but most televisions and cinemas use special glasses.

So-called active systems work by blocking each eye in turn when the image for the other is shown on the screen. It switches between the two eyes so fast that you won’t notice it.

The problem is that this system requires a monitor with a fast refresh rate, plus special glasses, both of which are expensive. The cheaper alternative is to use glasses that always block part of the image. In cinemas this is achieved using glasses with lenses that are polarised in different directions.

 

A simpler, cheaper technique that works with any computer monitor, TV or projector is to show the two images at once and filter them using coloured glasses. The disadvantage of this method is that you won’t see as many colours in photographs, but that’s a price worth paying for saving money on fancy special hardware. It also makes it much easier to share your creations as you won’t be dependent on others having 3D monitors as well.

You can read more about forms of 3D technology by clicking here for 3D television and what's available now and for how 3D TV and movies work, click here.