Virtual WalkAbout
Introduction
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How does a Walkabout Work?

Now that you have seen a working example of a walkabout, how do you create one yourself? Well, to create a walkabout all you need to do is take some photographs and make a note of their relationship to one another. In the example you have just seen, for instance, we would need to know that the first photograph of Beaghmore is taken looking north-east across the site, and that the second photograph is looking in the same direction, but several meters closer to the site (the photographer has simply moved a few paces forward to take the second picture); similarly, that for picture three the photographer has turned to the left to look across a cairn and and one of the circles, towards the north-west. The relationships build up as the number of photographs increase, becoming quite intricate.

Of course we can't just take photographs of an object at random. We need to have some 'rules' that will allow a computer to understand our movements. The simplest way to do this would be to create a grid and to take one photograph at each node of the grid. But in practice such a rigid approach often leads to difficulties - important aspects of the monument are overlooked, while other uninteresting features are given equal weight.

A more effective way to record a monument photographically is to allow the camera to move around the object more or less freely, so that only useful pictures are taken. This is what the Virtual Walkabout tool allows us to do. However, we still need to know from where each photograph is being taken, and to which other photographs it relates. To do this, the Virtual Walkabout uses a system of camera stations and camera movements.

Movement Description
Turn left Any turn between 0 and 90 degrees to the left (i.e. the camera deviates from the forward position). You remain at the same station
Step Left A side ways step to the left, but in the same plane (i.e. the camera still faces forward). This movement will take you to a new station
Forward A movement forward in the direction the camera is facing. This movement will take you to a new station
Turn right Any turn between 0 and 90 degrees to the right (i.e. the camera deviates from the forward position). You remain at the same station
Step right A side ways movement to the right, but in the same plane (i.e. the camera still faces forward). This movement will take you to a new station

Hints and Tips

In reality there are more movements that can be achieved. For instance, by moving forward and turning right both at the same time you effectively describe a rightward curve. This is a particularly useful move when recording objects with features on all sides, for you can effectively move the camera in a circle around it.