Photo Data Makes It A Snap To See What They Did
One of the most amazing things about digital photography is that each image is also a file, storing the information contained in each shot along with the photo, so you can load it up and see aperture settings, shutter speed, ISO, etc. any time you want.Do you want to become a better photographer? Just find images with the EXIF data intact and study what the pros used to make their shots look so darn pretty. Find out more about the process at Lifehacker.
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Focal length in particular can be misleading unless you know that what you are looking at is the whole of the frame. And of course that the exif data helps you (through the camera model) know the frame size.
But worse still for those trying this technique, most pros do at least a little post processing. This means that there's a lot more to the final image than the simple exif data might suggest.
However the biggest problem here is that the most important thing about a good photographer is that they have "the eye" for a great image. No amount of technical expertese will compensate if you don't have the eye.