Sometimes, beginning plein air painting students will wonder why my umbrella isn't set up to protect me from the sun. I suppose I must look a little foolish standing in the intense Arizona sun when I have a perfectly good umbrella at hand! But that's not what the umbrella is used for. Instead, it's used to shade palette and canvas so you can make more accurate color and value judgements.. If you have both in sunlight, not only is that hard on the eyes, but it is difficult to decide if a mixture is rich enough or light enough.
However, there's another use for the umbrella – to shield the eyes. When I paint someplace where the ground is very bright, such as a gravelly beach, I actually angle the umbrella down to block the light behind the easel. It's also good for blocking bright sun bouncing off a creek. This week, I painted down by Oak Creek, and I had both bright ground and a bright creek. Angling the umbrella to block this light made all the difference in the experience.
Here's the painting I made that day. If you're interested in purchasing it, it is currently up for auction at this link.
Hues of Spring, 9x12, pastel