Writers are always being asked, where do you get your ideas for stories? and the best answer is always "I dunno." Nevertheless, there are certainly exercises that can loosen imagination, and that's fun whether it leads to a finished story or not. Consider this picture of a small train traveling in the countryside toward encroaching shadows.
In today's anxious atmosphere, find five details that make it suggestively creepy (ominous shadows behind and in front of the train, off-kilter slant of train and parallel road, rust on the tracks and train wheels, station that makes no sense in relation to the tracks, what else?).
For a happier time, what in the picture suggests nostalgia or happy late-summer peacefulness?
Choose location for your literal point of view: the photographer's vantage point, the train, the station, where?
List possible characters for a center-of consciousness: a retired stationmaster, the ghost of a retired stationmaster, someone on the run spying from behind the weeds in the lower left-hand corner, the engineer, a passenger, three children who always wait on an overpass to wave at the train at five in the afternoon only one day it doesn't come. What do you know about him/her/they?
What tone of voice might your character use to a reader—eager, suspicious, defensive, inviting?
List ways the image itself could be included in a story: as a photograph, a memory, the literal setting for an action, a scene spotted from a car in passing—what?
Jot down as many observations and ideas as you can. Circle the ones that really jump out at you and join them together with arrows. Label the arrows with actions if they occur to you. And listen: do you hear a first sentence?
Whether it comes to you naturally or has to be cultivated, this kind of playfulness is at the heart of inventive storytelling. And the great reward is not necessarily "output," but rather the sheer joy of flexibility and discovery.
Hint: For Britain and Ireland, geograph has over six million photographs for armchair travelers or writers out to plunder scenes to prompt stories.