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Fly Eyes for Spying Cameras
Roland Piquepaille writes "Even with sophisticated cameras, we can sometimes get poor pictures. This usually happens because cameras use an average light setting to control brightness. When parts of a scene are much brighter than others, the result is that you don't catch accurately all the parts. According to National Geographic News, by mimicking how flies see, Australian researchers can now produce digital videos in which you can see every detail. This technique could be used to develop better video cameras, military target-detection systems and surveillance equipment. Read more for additional pictures and references about these future surveillance cameras."
Almost everything you wrote there is incorrect. The dynamic range of digital cameras isn't quite that bad and actually not significantly worse than film. The difference is mostly how film and CMOS sensors degrade when they're overexposed. You could use Photoshop to create HDR pictures, but there are better tools for the job. These pictures, or rather the low dynamic range pictures that are created from them, look odd due to limitations of the display systems, not our eyes. The algorithms, which compress the dynamic range into the range that a typical monitor or, even worse, a print can handle, mimic the way we adapt to high dynamic ranges in reality, but since a picture has no time dimension, they have to do spatially what we do over time, which creates the weirdness.
After capturing the image, you need to display it somehow, or else there's not much point to the exersize.
Current screens and prints have a tiny dynamic range, on the order of 1000:1
So, once you've captured that image, where the brigthest pixel is a million times brigther than the darkest pixel, how are you going to show it ?
There's only one answer: compress the range, that is, map your numbers (in range 1 - 1000000) to much smaller numbers.
Problem is, now you've got terrible contrast in the midtones. The problem is that compressing the range compresses this part of the range too. So, assuming the monitor can display 1000 different brigthnesses, you end up with a picture where the brigthest pixel in a face is say 404 and the darkest pixel is say 397. Which makes the face essentially monotone.