The watercolor paint I use most often-
- Hansa Yellow Medium
- Cadmium Yellow Lemon
- Yellow Ochre
- Cadmium Red Medium
- Quinacridone Rose
- Quinacridone Coral
- Quinacridone Burnt Orange
- Burnt Sienna
- Burnt Umber
- Terra Verte
- Green Gold
- Pthalo Green
- Cerulean Blue
- Cobalt Blue
- Ultramarine Blue
- Indigo
Those are the paints that are always squeezed out on my butcher tray palette. But wait- there's more! There are likely also some blobs of
- Perinone Orange
- Pyrrol Red
- Perylene Maroon
- Cobalt Green
- Viridian
- Emerald Green
- Sepia
- Manganese Blue
- Some Kind of Black (Lamp or Ivory or Carbon)
Plus maybe a few "convenience colors", some of 'em proprietary colors like Daniel Smith's Undersea Green, which is a mix of French Ultramarine and Quinacridone Gold that just looks purty. I've got a big tackle box full of paint tubes, some I've barely touched in years and some that I go through every few months. A few are no longer made, like Manganese Blue (toxic) and Green Gold (same, I think), but there are "hues" available, which is a near identical mix. The strangest tube of watercolor paint I've got is Red Lead, which is highly toxic and hasn't been made in years as an oil paint (I've got some old tubes that've since hardened) and should never have been made as a watercolor. It was stuck on a shelf at the old Pearl Paint in Alexandria, under the label for Cadmium Red, and I bought it so no one else would. I'm not about to use it either. The history of paint and pigments has some nasty things in it (like "mummy", which I leave to your imagination) and some intensely toxic substances. The most poisonous was the original Emerald Green, which was a bright, happy green good for foliage and grass. It was a copper arsenate, i.e. arsenic, and in the 19th century it was used as a house paint and for coloring wallpaper, and would off-gas when exposed to dampness. Yikes.
The piece of scrap paper up top is Arches 140# cold press, the paper I like best overall. Finding the right kind of paper for this kind of pen & ink and watercolor work, you fall between two stools; either it takes ink cleanly or it takes watercolors beautifully, and few papers do both. The cold press, with some tooth, can be too rough for pen & ink, therefor some prefer the hot press, which takes watercolor a little too weird and blotty for my taste (it's like the paint sits too far on top of the paper, but sinks in too fast).
Since John asked about this (see comment), I'll tell you. I draw a loose rough on thinnish paper, put it on the lightbox with the watercolor paper on top, draw it in ink (repeat as necessary till satisfied. Don' t overdo it, let the paint do some of the work or you're just coloring a drawing. Bo-ring), then I stretch it. This is so it can be painted without buckling. I do it like this; soak the drawn-on wc paper under the tap, both sides till all the surface is wet (this is where the importance of waterproof ink is vital), then attach it to a board. I've got this thing called a Zip-Strip (or something like that) that consists of a plywood board the size of a quarter sheet of wc paper and four plastic clamps that hammer into place along each edge, holding the paper till dry. The more common procedure is to tape it with brown tape (the kind you have to moisten) or staple it (I've got some heavy-duty foamcore board with a resin that makes is sturdy for stapling). Then wait an hour or so till it's good and dry and paint at will. When you pry it off the board it'll still be reasonably flat, with very little warping. The most enjoyable part of the process is soaking the drawing in the sink and seeing the ink turn glossy, though sometimes it's all I can do to keep myself from pushing it down the disposal.
Here are some fun links-