i test out new tubes of paint before i use them in painting. i take scrap rag board or canvas or masonite depending upon the medium i am using. i blob the tube colour in discrete units down one edge. on an edge across from that edge i blob on other colours in my palette particularly the whites and yellows i employ the most.
i start out by brushing the tube colour with medium until it fades away. i then reduce the colour on a separate line with the whites i set out. then i test the yellows. and if need be blues and reds.
quite often a tube colour when reduced with white will tend to get blue or green or amber. some siennas reduce out to a pinkish glow. others turn a sickly green. if you are trying to mix flesh colours, knowing how siennas behave in reduction can make a lot of difference. some alizarin crimsons reduce out to a blue while others reduce out to a golden.
i test out all new tubes. and i do not assume that the same pigment from different manufacturers will behave similarly.
there are great differences in the behaviour of tube paints in mixture. it is not possible to predict from body colour (straight from the tube) how the colour will behave as a tint or in admixture. sometimes the most expensive formulations can be the trickiest to control in mixing.
i tend to dislike the rigid systems i read about for colour mixing. yawn. by directed play and experimentation it is possible to learn very quickly what works. it is important to realise that colours in a tube are not the same as the primary colours in light itself.
melynda reid who wears hats but does not type caps
