Cameras have the questionable distinction of punishing their owners with some of the most horrid excuses for user interfaces ever devised by mankind. They are a good example of why you need to think in terms of your users’ mental models («for this picture, I want a shallow depth of field», or perhaps even just «I want stuff in the background to look blurry»), rather than the actual implementation model («you need to switch to aperture-priority mode and decrease the f-number in order to increase the aperture diameter»1).
I have no idea why camera interfaces are so bad, but this concept camera user interface by Miha Feuš offers some ideas on how to improve them.
Here’s an older video that shows more of his user interface.
Hope I didn’t get that backwards. I always forget. To be safe, I usually just take one picture at each extreme of the f-number scale, and then pick the one that looks right. (Update: Nikon offers a nice improvement here)
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