030/366: Liquid Optics

It's rained fairly steadily for the last couple of days, which is to be expected. This also sent me to the back yard in hopes of getting a very particular effect for the photo of the day, that I had seen on a poster from the APS's student photo contest a few years ago:

Water drops on the canopy on our deck, with little inverted images of the back yard. Water drops on the canopy on our deck, with little inverted images of the back yard.

Here you see a large-aperture shot of drops of water hanging off the edge of the canopy over the patio table on our deck. The drops are in focus, but the rest of the yard is blurred out. If you look closely at the drops, though, you can see tiny little in-focus images of the yard. Here's a zoomed-in section:

Close-up of the water drops, to show the images more clearly. Close-up of the water drops, to show the images more clearly.

On the right side of the drop, you see the tall arbor vitae bush that's right next to the deck, and the red-and-yellow awning of the kids' playset.

This happens because the drop is basically round and water has a higher index of refraction than air, so it acts like a tiny spherical lens. Which combines with the lens of the camera to make an in-focus image at the sensor of things that would be out of focus in the absence of the drop.

So, there's a nice combination of physics and aesthetics for a rainy mid-week day.

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