A small painting I was doing recently was ok in terms of composition, and I liked the basic concept, but it just didn't have any "life". I mused over it at this stage for several days...
Then, on the weekend I happened to drive past the site where I took the original photo. The difference now was that the light of early morning was streaming through the trees alongside the field--and suddenly I knew what was wrong with the painting--it needed a clearer light source! See how much better it looks with that added...
Later that same week, I prepared several underpaintings using a thin wash of oil paint, a technique learned from Richard McKinley at a workshop last October. I used Turpenoid, a non-toxic turpentine substitute, to thin the oil paints to almost watercolour consistency before blocking in the big shapes and colours for three paintings.
I had watched Richard use this technique in a demo, and after about ten minutes, with a little help from a hairdryer, the oil washes were dry enough to start adding pastel on top. So, why weren't mine drying?? I waited, and waited, and WAITED. Even the next day, the paper surface was still greasy and moist. Hmmm... Eventually the larger piece dried enough that I could complete a pastel painting on top, with some struggle to get the lighter colours to show. The pastel kept "melting" into the oil wash--what on earth had I done wrong? I abandoned the other two underpaintings until I could figure out the problem...
Finally I went back to the notes I took at Richard's workshop--and found the answer! He told us (and I even wrote it down but obviously didn't commit it to memory) that the BLUE can of Turpenoid is what you want--the green can (you guessed it, that's what I have) is unsuitable for this technique. Uh-huh. I don't know what the actual chemical difference is between the two, but you can bet I'll be donating my green can to my husband's shop and seeking out a blue can for pastel underpainting in future!
However, the other two underpaintings did EVENTUALLY dry--and here are the finished pastel paintings.