I finally had an opportunity last Monday to continue my experimentation with gouache as a cold-weather plein air medium, with unusual results.
(To see what I’ve learned so far about using this unusual medium, and for more details on the supplies I’m using, check out Part 1 and Part 2 of the experiment.)
I drove out to the Goat Creek trailhead, up the Spray Lakes road from Canmore, where the trail up the back of the imposing Ha Ling Peak begins. The view south from the parking lot looked down the valley behind Mount Rundle, with the steep and snowy Goat Range on the left and a shrub with interesting red bark in the foreground—not a bad place for an experiment. Convenient, too: I learned last time that my portable easel doesn’t lend itself well to gouache, which like watercolors, is applied to paper rather than canvas, and is very liquid when wet and could run if applied to a steeply sloping surface. (My easel isn’t very steady when it’s adjusted so that the paper block lies flat.) But here, I could just spread out my painting supplies on the trunk lid of my car, which is a very comfortable height.
I also found out that day that the lid of my gouache box detaches! This makes it much easier to hold and use as a palette.
This time, I tried glycerine as an antifreeze, although the temperatures hovered around the freezing point at Goat Creek (it was substantially warmer in Canmore, at the bottom of the valley). It’s one of the recommended additives, since it’s apparently also a component of watercolors and gouache. I used about a 25 percent solution, not wanting to add too much of the syrupy stuff in case it altered the consistency of the paint.
For the most part, the paint seemed pretty normal to work with, and I think I’m getting used to it’s characteristics. One thing that threw me at first was how much darker the colors get as gouache dries, but I’m getting more used to that now. It wasn’t drying quite as fast as usual, but I chalked that up to the colder temperatures.
I painted for over three hours, until a breeze kicked up that made it hard to hang onto my palette. I added the shrub in the foreground later.
Much later, in fact. There are two drawbacks to adding glycerine to paint.
- It’s hygroscopic—it pulls moisture from the surrounding air and absorbs it. This is probably why it’s also such a good moisturizer for chapped hands. I’ve even heard of it being used as a retarder, to lengthen the drying time of paint. I figured that since gouache typically dries almost instantly, this wouldn’t be a bad thing…but it was Thursday before I was able to finish the foreground and lay the painting on the scanner to digitize it. I checked on it again today and there are still a couple of spots that are sticky to the touch. This would probably be a conservation issue in the long term, as well as being annoying when carrying paintings home from a plein-air session that aren’t quite finished.
- It takes a lot of glycerine to work as an effective antifreeze, according to this chart of the freezing points of various solutions. A 25 percent solution only lowers the freezing point of water to -7 Celsius, or 19 Fahrenheit. It’s hard to stay out painting (standing in one spot, and probably repeatedly taking gloves on and off) for very long at temperatures much lower than that, but it’s worth noting.
There may not be many more winter painting days this year. The calendar calls Thursday the first day of spring, although Environment Canada also calls for snow that day. If I do get the chance, however, I’ll post about it here.