Public domain photos

The image shows a black and white photo of a man standing next to a ruler, holding a stick in his hand. On the left side of the image, there is a scale with different colors, and on the right side, there are a few color blocks.

The image shows a black and white photo of a man standing next to a ruler, holding a stick in his hand. On the left side of the image, there is a scale with different colors, and on the right side, there are a few color blocks.Open in library