Sure, anybody can make a two-hour plein air painting, but taking that painting and turning it into a large, finished studio piece is another matter entirely! "Just use a bigger brush" some might say. (Or, in this case, a bigger piece of pastel.) Going "large" involves refining composition, taking the time to correct errors that were made on-location, and more. As a teaser, I'm posting my plein air piece plus the finished studio piece below. You can see the full demo at my web site.
Here's the plein air piece (9x12):
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And here's the finished studio piece (19x25):