Pupils need to understand how some of the Toolbox works. Start with exercises using the Lasso tools to select an area of pixels. Click and drag a line around the object you wish to cut or copy. I prefer the Magnetic Lasso, which fastens itself to every subtle contour of the object.
Copy or cut the object on to another layer. Then create two layers and put one object on each. The Layers palette allows objects to be seamlessly combined. Each layer is like a sheet of tracing paper placed over another.
Layers are displayed as series of tiles in the Layers palette in the Menu.
For our project, a picture of the fourth plinth acted as the background layer. Source images from the internet or a digital camera, save them into files on a PC and from there, open them in Photoshop. Highlight the layer you wish to work on in this palette before going to the Menu and using colour balance, tonal balance, distortion, and so on. Click on Image and Enhance in the Menu for lists.
Our aim was to combine two objects convincingly and make them appear foreshortened. You can alter the opacity of a layer; the lower the value, the more you can see through to the layer beneath. A layer with a photo of grass on it, for example, can be made to appear as if it is growing from the surface of a house on another layer. Any plinth picture you find is likely to have a sculpture on it already.
Use the clone tool, represented by a stamp icon (located in the Toolbox), to clone a piece of the sky and simply paint it over the sculpture so the plinth eventually appears empty. Remember to turn off the other layers to aid you in this operation. Then, with the other layers turned back on, move the objects so that they now appear on top of the plinth. Use the Image tools to alter the perspective of your objects to fit the angle of the plinth.
Finally, use the Lasso tool to highlight and copy just the plinth (don't cut it out) on to an additional layer. Choose the order in which you wish the layers to lie; so you can place the base of the created sculpture behind the leading edge of the plinth, as in real life. Then merge the finished product into one. Warning: before doing this, make sure you save the multiple-layer version independently. There is no going back after merging. However, during the process of creation you can use the History palette to undo processes and try again.
Donald Short teaches at Moyles Court school, Hampshire