Color juxtaposition

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You are walking along a street.

The sight of something stops you.

In this case a combination of two bricks in a concrete block wall.
One brown, one blue.

Warm against cool.

Frame it so it resembles a flag.

There is always a reason why something attracts the eye.
In this case, juxtaposition of two colors almost opposite on the color wheel. They contrast and complement each other.

A good introduction to the color wheel is here.

Canon 5D Mk II, 70-200mm (150), f4, 1/500, Colonia del Sacramento,101014

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