Please don't be misled by the title of this post. It's purpose is not to say which is better between the two, but just point out what I know to be the differences and similarities between the two mediums.
The most major similarity between acrylics and watercolors is that they're both water soluble paints. That means they can be thinned with water and the brushes can be rinsed in water during painting sessions. Because of this, neither acrylics nor watercolors require the use of harsh chemicals so they're perfectly safe to let your kids play with, assuming they're old enough to know what not to put in their mouth of course;.
Also, both watercolor and acrylics are relatively cheap mediums to work in. Now, no quality art materials are cheap cheap, but these mediums are a lot less expensive to work in then say oil paints.
So those are the similarities. Now for the differences. While all watercolor paint I've personally encountered pretty much has the same type of texture, acrylic paint comes in three varieties, "light viscosity", often labeled "fluid" or "soft body", medium viscosity, and heavy viscosity, often labeled "heavy body". According to manufacturers, the light viscosity acrylic paints are better for glazing for more realistic styles, while the heavy viscosity paints are better for impasto and impressionistic styles because they hold brushstrokes very clearly. If you like painting with a palette knife, a heavy body paint is definitely the way to go.
A glazed effect is pretty easy to achieve with watercolor, because tend the put the paint on transparent. You can't really achieve an impasto look with watercolor, though, unless you layed the paint on so thick that it looked more like an acrylic or oil painting. But if you're going to do that, you might as well work with oils or acrylics. So in that sense, acrylics are more versatile than watercolors. That's not to say that you can't achieve a wide variety of styles in watercolor, though. But, if you like to paint in a style with bold brush strokes, you probably won't enjoy working in watercolor, since the nature of the paint interacting with the water tends to blend those out automatically.
While writing this, I decided to do a google images search for "watercolor impasto" and I found pictures of watercolor paintings and impasto oil paintings separately.
While there are watercolor canvases and acrylic papers, generally speaking most watercolor painting seems to be done on paper and most acrylic painting tends to be done on canvas. Acrylic paper doesn't seem to be good for much of anything other than practice anyway, so there.
Another major difference is in the histories of both mediums. It wasn't as popular or as prestigious as oil paint, but watercolors have been around since ancient times. Albrecht Durer is known to have done them. Acrylics, on the other hand, as we know them, have only been around since about the 1950s.
*Watercolor paints are comprised of just pigment and water, whereas acrylics also have a polymer called acrylic mixed into them, hence their name, which accounts for their more oil paint like texture.
How I Work With Each Medium
When I work in acrylics, I usually work on canvas. Sometimes I might work on board, but I never work on paper with this medium. I use a smooth glass palette without any wells, because I'm not going to be adding a lot of water to my paint. I'll usually thin the paint with some acrylic medium, or add just enough water to thin the paint without making it runny. In the gallery below, you can see both what that paint would like like on my palette and on the canvas. I achieve this by adding little bits of water at a time with a brush.
When I'm working in watercolor on the other hand, I use a little spray bottle to load that paint down like crazy with water. When working in watecolor, you should expect to put so much water in the paint that the paints would run into each other if they weren't separated. That's why palettes made for watercolor have wells or compartments for individual colors. I'm including a pic of my watercolor paint in my palette after I've mixed water into it. You'll see that the paint runs along the edges of the compartment, because there's so much water. Note:If you already have a palette like this and want to try acrylics, you can definitely use it for that. I prefer the large glass palettes, though just because they're so much easier to mix on and clean.
When working in acrylics I don't put anything on the surface under the paint, unless it needs to be gessoed. When I work in watercolor, though, I usually find it very helpful to wet the area I'm working on before putting the paint on top. It just seems to flow much better that way.
Here's some paint put directly on the paper
and here's some paint put down after wetting the paper.
As far as how I actually paint, how I move the brush and stuff, that's pretty much the same with both mediums. The difference is in how I prepare the paint on my palette and how, or even if, I prepare my surface for the paint.
So those are the similarities and differences between watercolor and acrylic paints and how I work with both. That's all for now. I'll talk to you again next week.
*Since writing this post, I've learned that watercolor paints also include gum arabic and additives like glycerine, ox gall, honey, and preservatives.
Painter of portraits and wildlife