Creating and sensibly applying contrasts
Contrasts can be created in different ways. For example, a combination of a natural and a very engineered figure can constitute a contrast - or the combination of a very big and a small element. These two examples are not applicable to logo design without fail, but the following examples are:
Contrasts develop when coloured elements are mixed with black-and-white elements. This can be considered for logo design, but you should always keep in mind that the logo may be used just in black-and-white in some cases (e.g. for faxes). In those cases, the effect of this contrast - and possibly the effect of the whole logo - may be lost.
In logo design, line thickness - or the combination of thin elements with thick elements - is a very good way of creating contrasts. If they are wisely used, they result in a good outcome in conjunction with proper spatial partitioning.
