When designing a logo, you should also keep in mind that the wrong combinatoin of colours, or the overlap of two colours may cause unaesthetic effects because of gauge-pin difficulties.

If, for example, a black word is partly overlapped by a red word, shifts that occur while printing may cause white "flashes".

The effect would be even worse if the before-mentioned black writing was blue. A downward shift would create white flashes at the head. At the same time, both colours would be printed upon each other in the bottom, and result in an unaesthetic grey.

The solution of these problems:

If one of the two colours is black, it could be set to over printing. Another approach would be to use the same colour and screen one onto the other, i.e. to use a lighter shade of the same colour.