I was sent a set of five, 15ml tubes to test. The colours sent were:- Cadmium Yellow Deep, a rich opaque colour with an orange bias. Cadmium Red Light, again opaque with an orange bias. Cobalt Blue Light, a semi opaque colour, and two earth colours; Burnt Sienna and Burnt Umber both semi opaque.
(Right to left in the example below.)
However, if opaque paints are used in a more direct approach, as I have done here, they are easier to control than transparent paints and the fact that they lift more easily means you can lift highlights out of wet or dry washes. Opaque paints are "slow movers" so the wet-in-wet technique would be more easily controllable, if that's your thing. Personally I prefer my paint to be more free flowing.
Opaque paint can, of course, be used in conjunction with transparent paint. I recommend artists get to know the different qualities of the paints and select their colours accordingly. This is explained further in my article on painting with a Limited Palette.
It is also worth noting that paint manufacturers sometimes use the same, or similar, names for their colours, but the actual colours may not look the same, so check before buying.
My usual palette consists of three cool primary colours with the addition of three warm earth colours. My reason for this is simple; I can make a cool primary colour warm, by adding red, but I cannot take the red out of warm primary colour to make it cool. This makes warm primary colours less versatile in a limited palette of paints. It is necessary to understand Colour theory in order to understand the difference between a warm and cool colour when buying paint.
Which one brand of paint would you recommend? Or do you have a few different brands in your palette?