Watercolor purists would never even think of using anything opaque. For the most part I am like minded. Once you start depending on being able to work light on top of dark, you lose a lot of the wonder and magic of watercolors. Part of the beauty of the medium is that transcendent glow that can only be achieved by working with the transparency of the colors.
There are times however when I find that using a touch of white can be useful and enhance a piece if used spareingly. There are numerous things you can use:
* white watercolor from a tube (but this is still fairly translucent)
* white gouache
* white-out (you can buy it in a pen-form)
* white gel pens (my personal favorite)
You can find white gel pens at stationary stores, (although unless it's a specialty store, the selection of brands will be limited) or art stores, or online (jetpens.com is a site I love). My current favorite brand for the techniques I'm showing you here is
Y&C Gel Xtreme.
Unfortunately I haven't located a good source for them online - I purchased mine from a local Kinokuniya store. I like this brand in particular because you'll find if you try this that various brands of gel pens will differ greatly in how easily they get clogged, how smoothly the ink rolls, as well as the opacity of the ink. Some brands are so translucent that it doesn't even feel worthwhile. The other brand I have in the picture above is
uni-ball Signo. The ink is a bit less opaque, but it's serviceable.
You can click on the photos below to view them at high resolution. The details that I talk about are a little hard to see at smaller sizes.
Working Into Wet(1) This is a technique I like to use. I start by painting the area that I'm working in, shading normally and using the transparency of the watercolors. Note that with these gel pen techniques I'm talking about here I'm
not replacing the transparency of the paints or compensating for "forgetting" to leave whites. I feel it is more of a complement to the other techniques being employed.
(2) While the area is still wet I add in some scribbled highlights. As it dries the wetness of the underpaint leaches the white out a little bit, softening the edges.
(3) I go back in after it has dried and brighten up some areas with a second layer of gelpen on the dry surface.
Working Into Dry(4) For harder more defined edges I just draw directly into dried areas.
(5) (6) You can see I've done this in numerous places in this piece.
(7) After drawing some loose textures with the pen, I go back in with dark color on a brush and paint in some more layers of color around the pen lines. This makes the white really pop out some more by contrast. I also sometimes brush clean water along the edges of where I've drawn the white to blend it out into the surrounding colors a bit better and make the transitions more subtle. You can even just use your finger to blend a little bit right after you've drawn, while the ink is still wet - smear it outwards a bit.