Someone last night asked me about HDR setting on his camera, but I was tired and distracted so I dont remember who, only that it was a poor, rushed response. Basically the contrast level between different colors changes alot depending on how much light they exposed to. In a bright room, blue and off-blue will both look similar but faded, but in a dark room they will be richer and the difference between them will more noticeable (but the room is dark, which is bad for photography). This is one of the reasons why everything looks prettier at sunset (not just the sunset itself, but even the air looks nice), because its just the right balance between lighting and contrast (aesthetically, at least). Digital cameras, however, typically operate using sensors which cannot handle quite as much of a range of contrasts as the human eye, causing the photo to look a little bit flatter, ESPECIALLY in situations where part of the photo is dark and the other is light (such as the sun peeking over a hill and only illuminating part of it). This is why purists prefer film - 35mm captures about the same contrast range as the human eye. High Dynamic Range is a setting which takes 3 photos (typically at -0.7, 0, and 0.7 EV), one dark, one normal, and one bright. It can do this by either adjusting the aperture (widening or tightening the camera pupil) or by extending the exposure time by a few milliseconds. By taking these three shots, and then using some fancy software to combine them, the resulting photo actually has a /greater/ contrast range than the human eye. If you take a photo in an all dark or all bright situation, you probably wont see a difference. But HDR photos with a good bit of shadows in them will actually produce a photo which is more colouful and gripping than if you were looking at the same subject with your bare eyes.
Posted on: Sat, 19 Jul 2014 17:47:16 +0000