Re: Watercolor paints with very little water?
There isn't a real difference between gouache and watercolor, both come with and without chalk, both usually are made with pigment, gum arabic and the same additives. If you look at the packaging you will see gouache often labeled with "opaque watercolor", the reality is it's just another branch of this medium ( our forum even includes a gouache thread )
The difference is that gouache is using more opaque pigments, and pigments ground coarsely to emphasize their opacity, and watercolors are ground to a much finer size to emphasize their transparency. You see similar differences between lines of watercolor paints - lukas uses chalk for example in their artist grade watercolors, while Schmincke Horadam grinds their to the point even ultramarine starts to become staining ( ultramarine finest ), and it's based on who their customers cater to. Each brands line is designed around a specific set of tastes, which is why some artists strongly prefer a given brand. The customers who buy gouache prefer more opaque pigments, they are often illustrators who need to scan their work, and thus prefer a matte finish that is easer to scan.
High end gouache like winsor newton does not use chalk, fillers and the like, they achieve what they are doing via using more pigment, and adjusting how the colors are ground - the liquid portion can be exactly the same.
Now gouache using artists often use white - which is seen as a sin by many watercolors - to achieve changes in value, but then this is something the watercolor masters we revere so much today did as well.
Further some pigments are opaque in watercolor, and are just about the same stuff in gouache - so you have some cases where the same color is the same stuff in both mediums. I was for example using WN Permament White in Gouache - I compared to QoR Titanium White, for all intents and purposes it's the exact same stuff, just as opaque, no material difference in usage. The same is true with some other colors like cadmium and oxide of chromium.
You CANNOT work thickly in watercolor or gouache, that is because gum arabic isn't a flexible layer of paint like acrylic is, it's not even a medium which dries to a layer, rather it's purpose is to "glue" the watercolor pigment particles to the paper. Further if you apply another thick layer, what is underneath rewets as well unlike acrylics. Watercolors are much closer to pastels in that it's just the pigment on the surface ( the gum arabic absorbs into the paper and binds the particles from the bottom, this is also why paint dries lighter ). You can use it thickly, but when you do it gives the resulting color a dull unappealing appearance, and it can and will crack.
However there are three solutions for this, the first is using watercolor impasto medium, which I have no idea what it's about.
The other is using QoR watercolors, since they don't use Gum Arabic. They use Aquazol which unlike watercolors can be used thickly and it won't crack. However if you use it this way it will result in a dull carbon appearance ( instead of the more satin velvety finish a top quality luminous watercolor will achieve ). The other benefit is it does not dry lighter to the same degree since there is actually a "layer" of medium which refracts color at the same index as water.
Now the third solution is more of a trick, if you do things thickly, do them so small they cannot crack - so you can use blobs of thick paint, often in opaque colors, to create stars, flashes of color, what Joseph Zbukvic would call jewels. Try painting thickly and observing what happens on paper after a week or so, you should get an idea from this how big you can make things without problems occurring.
Golden caters to acrylic painters mainly ( their primary product is acrylic paints ), but it seems to me that they are catering to that market in their watercolor line - the artists they had do product feedback seemed like they were current acrylic customers - frankly this resulted in something many established watercolorists don't like, something different, but this is exactly what we need, more options. Frankly my goal in this medium is to display my work with and next to other mediums - and those other mediums have far greater range of values, and can easily create more visual power due to their varnishes, glazing and impasto, so I welcome anything that gives me more options to increae the visual impact of this medium.