How to see 3D photos
Photography has an inherent limitation in that cameras typically capture images that don’t have any true three dimensional depth. We have two eyes, but with the exception of specialised equipment, cameras only have one lens. There are ways to “cheat” however, and for almost as long as there have been cameras, there have been people trying to find ways to take and view 3D photos.
3D photography is experiencing a rush of interest and innovation, as more people experiment with better digital cameras, and a wave of new 3D movies, including the spectacular 3D epic by James Cameron, Avatar captivates audiences worldwide. 3D is the next big thing, and many want to create and see 3D photography, or stereophotography.
This article is not a history of stereophotography. The point is to teach you how to see 3D photos on the web. There are many different ways to see 3D, with just as many gadgets to help. The technique I will be showing you requires no special equipment. All you need to do is train your eyes to look at these images in what you might call an “unnatural” way.
Table of Contents
- Stereo Pairs
- How to do it
- Try it!
- Linking to this guide
- Some more examples to enjoy
Note: This technique will be impossible for some people. If you have poor eye control, a dramatic disparity in eye function or anything along those lines, you may not be able to see the 3D effect no matter how much you practice.
Now that we’ve cleared that up, lets learn how to see in 3D!
To see a 3D image, each eye needs to see a different view. There are ways to take photos like this, but I’ll talk about that another time. When the two slightly different images are processed, they are placed side-by-side so that the viewer can use a special “crossed-eye” technique to overlap them, and see both views together in 3D.
Below is an animation that simulates what it looks like when you view these images in 3D. The instructions follow.
How to do it
- Sit square in front of your monitor, with the image directly in front of you, at about arm’s length
- Sitting further back makes it easier – you don’t need to cross your eyes as much – but makes the image look smaller
- Make sure you keep your head level horizontally, tilting your head will prevent you from merging the images
- While keeping the stereo pair of images in the centre of your vision, slowly cross your eyes
- The stereo pair will go out of focus and you will seem to see four images, as shown in the animation above
- If you find it hard to cross your eyes, it can help to hold a pen in front of you and look at the tip with the stereo pair in the background
- Gradually cross your eyes more and more – if using a pen to assist, start it close to the monitor and move it towards your nose
- Continue crossing your eyes more, untill the centre two of the four images overlap and you see three blurry images, as in the animation above
- Try and hold the centre image together – it is possible to “lock” it in place and see it as one image
- The “locked” centre image should appear in 3D!
- Now the tricky part, focus – while holding the 3D image in place, relax your eyes – drop the pen from your field of view if you are using it
- If you can keep the 3D image locked and relax your eyes, it should eventually pop into focus, as in the last frame of the animation above
What you are doing here is causing your eyes to look at a space between you and the monitor, but focusing the lenses on the monitor. Our eyes never naturally need to do this, so it can be tricky to do at first.
Try and see the 3D effect yourself with the stereo pair below.
How did you go? If you were able to see the effect, congratulations! It really is very striking isn’t it? If you couldn’t manage to do it after trying for a while, leave it aside and try again tomorrow. It can be tricky to get the first time, but the majority of people can do it. If you find you are unable to see the 3D effect no matter how many times you try, then it may be that you are one of the few who for whatever reason will never be able to do it. I have no idea why, some people can’t curl their tongues! *shrug*
Linking to this guide
If you take 3D photos yourself (I teach you how in this article), then please feel free to link to this article to give your viewers a clear, straightforward guide to seeing your 3D images. Just copy and paste the following code into the image description on Flickr or whatever image sharing service you use: