Let's take a closer look at The Course of Empire: Destruction by Thomas Cole. I'll cover:
Date created: 1836
Dimensions: 39 1⁄2 × 63 1⁄2 inches
Medium: Oil on canvas
Below are the main colors used in the painting. Copy the hex code for use in Photoshop or other editing software.
(You can check the color palette of paintings using this tool by Adobe.)
Here's the painting in grayscale so you can clearly see the different values (lights and shadows):
(Use this free image tool to apply a grid and grayscale to photos of your paintings.)
Below is the painting with a grid over the top so we can analyze it in terms of the rule of thirds. The grid lines and intersections are considered aesthetically pleasing areas.
Here are some similar paintings by Cole:
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