One of the main advantages of a digital camera is the LCD monitor screen on the back. The screen provides instant feedback, so immediately after you've taken an image you can see if your composition and exposure were correct.

You can shoot, check and adjust until you've got everything right. But if you only use the screen for reviewing your images, you're missing out on other helpful features.

TFT or LCD?

Canon refers to the screen as the LCD (Liquid Crystal Display) monitor, but it little resembles the calculator or watch screens from the 1980s. It can display colour for a start. These new types of screen are known as TFT-LCD (thin film transistor) screens, and are the type found on flat screen computer monitors. They consist of an array of pixels aligned in rows and columns.

A TFT-LCD screen is made up of a film of transistor switches applied to each pixel that makes up the LCD. The transistors are used to control each pixel individually, allowing them to be switched on or off without affecting the surrounding pixels. The delicate electronics of the LCD are protected behind toughened glass.

Resolution

The clarity of the image on the monitor is determined by the number of pixels in the screen. More pixels give improved resolution. However, bigger screens need more pixels than small screens to give similar resolution, so the number of pixels alone does not give any guide to the resolution of the screen on your camera.

The monitors continually evolve. They are now larger, brighter, and have a better angle-of-view than on the earliest models. The angle-of-view describes how far away from the central axis of the screen you can view your image without it suffering from distortion in colour or brightness. The viewing angle of the EOS 5D, for example, is 170° both horizontally and vertically. This compares to a viewing angle of only 80° on the EOS 20D.

Setting the display brightness

Display brightness is something you may need to change from time to time, depending on the shooting conditions. Low screen brightness is good indoors when the ambient light is low, but will be washed out by bright sunlight. There is no correct screen brightness – just set the level that is comfortable for you. The early cameras – the EOS D30 and EOS D60 – had only two brightness levels: standard and bright. In the subsequent models, this was increased to five levels, allowing you to see the screen more easily in a wider range of lighting conditions. With the latest models, the EOS-1D Mark IV and 1Ds Mark III and the EOS 40D and 50D, technology has improved and they now offer 7 levels of brightness adjustment.

EOS-1D Mark IV, 1D Mark III, 1Ds Mark III, EOS 40D and EOS 50D

1. Press Menu button
2. Use the joystick or main command wheel to scroll to the second yellow settings tab
3. Use the rear control dial to select LCD Brightness
4. Press Set
5. Use the rear command dial to adjust the brightness
6. Press set to lock the brightness setting

EOS 1D and 1Ds series up to Mark II

1. Press and hold the Menu button
2. Rotate the rear control dial until you have the Setup tab (1D, 1Ds) or Setup tab 2 (1D Mark II, 1D Mark II N, 1Ds Mark II) displayed
3. Press and hold Select button
4. Rotate the rear control dial until LCD brightness is selected
5. Press Select to enter the brightness setting and use the rear control dial to alter the brightness
6. Release Select button to set the brightness level.

EOS D30, D60, 10D, 20D, 20Da, 30D and 5D

1. Press the menu button
2. Rotate the rear control dial until LCD brightness is selected
3. Press Set
4. Rotate the rear control dial to alter the brightness
5. Press Set again to lock the brightness level.

EOS 300D, 350D and 400D

1. Press the menu button
2. Press the jump button until the Set-up tab is displayed (third from the left on the EOS 300D, fourth from the left on the 350D and 400D)