The Red Window And The Gas Gauge
We used have them - on the back of old roll-film box cameras. The red celluloid window let you see - dimly - the numbers on the back of 620, 120, 0r other paper-backed films. You got words and dots warning you to beware of the start of he film, then numbers as the film wound past the square throat of the camera and then another set of dots to tell you it was done and to wind the trailing paper on before you removed the roll.
It was a wonderful way to concentrate the mind and sharpen the skill - having 10, 12. 0r 16 shots only on the roll meant you had to do it right each time - no flapping about with a dozen shots and pick the best out later. You couldn't shoot 12 similar shots to get one good one. If you were a kid you had one roll of film for the entire summer vacation and it had to record 3 months of your life.
We also need a gas gauge. Not a petrol warning light - not an LCD icon of a half of an AA battery - a gas gauge. When we had a dial with a needle that swung from full to half to empty we watched it closely - again the one tank of gas might have lasted the entire summer if we were prepared to take the trolley bus and walk as well. We need that gas gauge on the back of the digital camera to tell us what the battery is REALLY doing.
Some camera makers have done better than others. A big Nikon DLSR will have a battery measurement window accessible through the menu and will give an actual percentage of charge left on the battery. Presuming it to be accurate, it means that you can know whether you have enough juice for the shoot before you start.
Other makers give us little battery icons and they don't even agree amongst themselves what the divisions might mean. Good for the shop - we can sell more batteries to those who are nervous about it. But if they can include dog face recognition and miniature effect backlighting for fireworks in HDR macro at a touch of slightly dubious finger...surely they can give us an accurate and readable numeric battery display.