Redditor comments:

The second one is the reflection in the pond. If you look at the trees you'll see the ripples in the water.

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Original is right side up. It is then turned upside down. You can look at the mist, or you can tell by how much light is coming from the sky. It's really bright in the original because you're getting direct sunlight reflecting off the clouds. In the reflection of the pond, more of the light goes through the surface of the water reducing the glare of the sun.