These were part of a first year project looking into light and space. There are many visual cues involved in interpreting the layout of a space. These cues enable interaction with a space and the objects in it, and they’re mostly taken for granted. For example, someone entering a room will see lines, corners and different types of light and shadow all of which help them to move around in it. The project took a look at some of these cues and explored the possibility of coercing them to produce unexpected results.

The image on the left shows a very simple arrangement of blocks lit by a single light source. It’s fairly easy to make out the blocks and the scene is unremarkable.

The same scene viewed from a point near the light source is shown on the right and it becomes a lot harder to make out the blocks.

So what’s going on?

Things become a little clearer with a projected image.

The image on the left is distorted by the blocks as would be expected, but when we move back to a point near the light source (the projector) this distortion is much reduced and the blocks become almost impossible to make out. It’s obvious that an uneven surface will distort an image projected onto it, but what isn’t so obvious is that moving closer to the point where its projected from will reduce this distortion.

The same principle can be used in a space.

The lines on the left look unremarkable, as they would from most viewpoints. However, when looked at from a particular point they appear to straighten and move into the wall.

This can be taken advantage of to create a similar illusion with something a little more complex.

Again, it appears to move into the wall. This phenomenon is known as anamorphic perspective.

A distorted or uneven surface isn’t necessary to produce this effect, here we have a quadrangle which looks like a square when viewed from a particular point. This use of perspective appears in Hans Holbien’s well known painting The Ambassadors.

Anamorphic perspective can also be used on a more complex surface.

The background walls can be used too.

And it can be used to make more complex structures.

The same principle can also be used with a smooth reflective surface. The reflection distorts the space around it, but this process can be reversed.

Anamorphic perspective can be used to change the characteristics of a space, or at least to create an illusion that does so. This begs the question, can something similar be done with light?

Say we want to project a stripe like the one in the left image below and also eliminate the shadow in it, completing the illusion. Additive light (eg light from a bulb or projector) can be expressed as a combination of red, green and blue light. The scene is being lit with a household bulb, so the reflected light will have some component of each of these colours. Now, we want to project a red line, meaning no green or blue light can be used. But that’ll mean only the red portion of the shadow can be eliminated, so red additive light alone won’t suffice.

We can get around this by projecting on to a red surface rather than a white one so that only red light will be reflected from it. This means that the shadow can be eliminated by projecting enough red light to make up the difference caused by it. Doing this almost eliminates the shadow in the red part of the image on the right.

Using visual cues in the manner described above may seem a bit contrived, but the same phenomena are in everyday surroundings. The photo below shows sunlight entering from a window and being broken up by the surfaces it lands on. Similarly to the image projected on to the blocks, there is a point from which this can be viewed where it won’t get broken up.

The image on the left shows a shadow from a drill on a plain surface. Adding another surface distorts the shadow, similarly to the way that the sunlight above is broken up.

Looking at the shadow from a point near the light source, the distortion is much reduced.

These interactions between light and structure are everywhere, seeing them is just a matter of looking.