Read all about it at Compound Eye:
I have engineered a fair number of inexpensive DIY camera hacks. This one is by far the cheapest: it’s free! Simply place a drop of water on the phone’s lens, carefully turn the device over, and the suspended droplet serves as a liquid lens.
There’s a diy laser application going the other direction. Shine your laser pointer through a droplet of water and you cast a large image on the wall with microscopic detail of the droplet contents….Best if you have something living in droplet…
example
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