Gweebarra River I, Portnoo, Donegal

That last crescent of sand was maybe twenty minutes from disappearing. The tide was already reclaiming the Gweebarra estuary, flowing across the submerged banks in sheets of turquoise, and only this one pale sliver was still holding above the waterline. Small waves breaking gently across its surface.

Looking straight down changes everything. No horizon, no sky, no sense of scale. The deeper channels between the sandbanks read as dark teal curves, the shallow water over sand glows turquoise, and that final exposed crescent anchors the whole composition. From ground level this is a fairly typical Donegal estuary. From directly above, it becomes something closer to abstract painting.

Conditions had to be calm for this to work. Any chop on the surface and you lose the colour separation between deep and shallow water. The light was soft and even, which let the natural palette do all the work. No fighting with hard shadows.

An hour later, every sandbank was gone. Six hours after that, they'd be back. The whole composition is temporary, and I caught it at the moment when just enough sand remained to hold the image together, with the Atlantic quietly taking the rest!