This was a botched photograph of a Flabellina affinis when I forgot to zoom through. (Note that it's still at 24 mm—still fully zoomed out.) But I like the riot of colours. This is on the Bristol Beaufighter.
Wed Apr 10 06:51:01 2019
15°C, depth 37 m
Il Merkanti, Malta
f/10.0, 1/1600, ISO 100, 24 mm
Wet lens: AOI UWL-09 Wide Angle