Shadows - to use or not to use?
Shadows can give an interesting three-dimensional effect to objects on our presentation visuals. But too much use of shadows can make our visuals look cluttered. So we must be caution when applying shadows to text or images on our presentation visuals.
A general rule is that shadows are better applied to large objects. Applying shadows to objects that are too small will make the overall visual look cluttered. This is true especially for small text objects.
Another area where shadows will help is when there is not enough contrast between foreground object and the slide background. Adding a shadow in this case will increase the visibility of the foreground object.
Here are a few illustrated examples on when to use or not to use shadows on your visuals.
Shadows on large objects. Shadows applied on large objects makes the object float up and give a three-dimensional effect.
Shadows on small objects. Do not use shadows on objects that are too small. Notice that in the illustration below, the small text is difficult to read after adding shadows.
Use shadow to increase visibility. You can add a shadow to foreground objects that colour is very close to the background colour. This will increase the visibility of the foreground objects as you can see in this example.
Use shadows selectively and when necessary to enhance your presentation design. Always remember that it is better to have clearer visuals that your audience can see than to have visuals that are complex and difficult to read.