When tinting, a concentrated tinting colour is mixed into a white or light base paint until the desired shade is reached. In practice this is now usually done by machine: at the paint-mixing station in a specialist shop, a reproducible amount of pigment is dosed according to an exact recipe (colour code, e.g. NCS or RAL) and blended with a shaker. This means the same shade can be reordered later without any problem – important when a wall needs patching or another tin is required.
Tinting by hand is also possible, for example with tinting concentrate from a bottle. The disadvantage: the colour is hard to reproduce exactly, and you always have to mix enough material at once to avoid colour differences between tins. There is also the rule of thumb that the maximum pigment proportion is limited – too much tinting colour can impair the covering power, gloss level and abrasion resistance of the wall paint. Very strong, saturated shades are therefore better bought as ready-tinted full-tone paint.
The process at the specialist shop: choose the shade (colour fan or sample), determine the base paint and quantity, enter the recipe on the machine, tint and shake. It is important to make a test coat on the wall after tinting and let it dry, because shades look different wet than dry and vary depending on the lighting in the room.
Tinting is worthwhile whenever an individual, non-standard shade is desired or when only small quantities of a particular colour are needed. For common standard shades, ready-mixed paint is often cheaper and more colour-reliable.
Machine tinting at a specialist shop usually costs only a few francs surcharge per container depending on quantity and colour depth; the main cost factor remains the wall paint itself and the painting work (guide values, no guarantee).