High Dynamic Range (HDR)

When discussing HDRI (High Dynamic Range Imaging), it's probably best to start out with what the term 'Dynamic' means. 'Dynamic' - pertaining to or characterized by energy or effective action; vigorously active or forceful; energetic. So, you may translate this into the realm of photography by comparing the 'dynamic range' to how much the shadows and highlight areas of a given image can yield visible and quality information-- so the more shadow, mid-tone and highlight detail a photograph has, the more 'range' of information it shows, thus the high 'dynamic range' it yields.

The common misconception most people have to HDR it they think, the only way to achieve such a shot is to take three or more separately exposed images and layer them. Once layered, you and your software can begin to decide how much from each exposure you choose to show, thus eventually bringing about a visual of extreme shadows and blown-out highlights with perfect detail and a more balanced exposure. The problem here is this: we as humans already see the world in HDR and 3D, so when a photograph is transferred to HDR, it usually is going to look fake and most people who try HDR always overdue it anyways. My problem with the layering style of HDR is, well, it is fake... In many cases it just seems like a cheat to not lighting your subject correctly or waiting for the right time of day.

When we speak of dynamic range in the realm of digital cameras we are talking about how much shadow to highlight information a digital sensor will capture. A 1.4crop Nikon sensor isn't a bad sensor, as it captures just as many megapixels as all the others. Were in comparison it lacks quality is the 'stops' of light it captures, where a full frame sensor would do a little better. A big reason why top-of-the-line photographers shoot with medium format digital camera isn't just because of the megapixels-- the sensors are much larger and thus can capture far better range of info between shadows and highlights.

As I mentioned earlier, I don't work in the realm of HDR very much. If I began shooting more architectural work, I would most likely be working with this technique a bit more often. As I shoot people more than architecture and am usually patient enough to wait for the right time of day to capture my nature images-- I don't have many of these style images. Below I included an image that, even with waiting for another time of the day, would have not gotten as good a shot as this. In this case, I had to shoot multiple exposures as I was shooting into the sun. My camera just can't handle both these extreme shadows and the bright light created by the sun within one image.

So, to put everything into context: HDR can be a well-balanced-flash lit image, correctly balanced daylight (e.g. right time of day) for even lighting, multiple images layered together... or an extremely expensive and awesome medium/large format digital sensor. All these styles of photography yield a higher dynamic range of information than most standard snap-shots and thus constitute a HDRI (high-dynamic-range-image.)

I hope some of this was useful to you... If you have any questions or concerns, please e-mail me anytime you like! kroghstudios@gmail.com

Yellowstone National Park
6:10am-- September 28, 2011

Nikon D90, 100 ISO, f/16
3 layered images each 1stop apart using shutter-speed

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