Getting the best light on your artwork while sketching outdoors makes a huge difference for seeing color. Ideally you want soft, diffused white sunlight at a level close to the brightness of the scene itself. The worst thing is cast shadows or dappled light across the painting.
Controlling the light on your work can be difficult on a bright sunny day, which is why I came up with this easel-mounted diffuser. Unlike a white umbrella, this setup won't blow over in heavy wind. The diffuser affects the light only where you need it.
Pendaflex frame. These rectangular aluminum supports were used for hanging file folders. Over the frame I stretched white rip-stop nylon and sewed a seam around the edge. The angle of the diffuser is completely adjustable and the whole thing is removable, held in by a wood bracket at the top of the easel.
Southco adjustable hinge, so that the whole bracket can fold down out of the way.
contre-jour (facing the light), so the diffuser brings nice white light to my work surface.
I documented the whole thing on video, and I'll be releasing that segment as part of an upcoming DVD/download on plein-air watercolor.
If you make one of these diffusers, please send me photos of how you adapted the idea.