Bracketing refers to taking a set of photos and changing only 1 setting in the Exposure Triangle (typically the shutter speed) to achieve a set with a range of 1, 3, 5, or even 7 EV so that you have some underexposed images, some overexposed images, and some just in the middle. There are dedicated stand-alone software and software plug-ins that can create high dynamic range images from a carefully constructed set of “bracketed” photographs.
But the technique is dated, has limited use, and is particularly challenging when used in scenes with non-linear horizons (mountains) or when vertical objects such as trees or buildings get in the way. These filters and their application in landscape photography was invented in the 1970s by the late master Galen Rowell. Some photographers use plastic or glass GND filters to expose for the shadows of an image that also has bright areas, placing the filter in front of their camera’s lens to diminish the portion of the image with bright highlights – typically the upper half. There are three ways to overcome the camera’s limited dynamic range: Graduated Neutral Density (GND) Filters Given that limitation, what can we do with today’s modern cameras to go about increasing dynamic range in our photographs and achieve a High Dynamic Range, or HDR, image? Some of the newly-manufactured cinema cameras, like the Red Weapon, are beginning to push above 16 stops and closer to the 18-stop range. In fact, the human eye can see about 20 stops (EV) of dark/light difference, whereas the best modern digital SLR camera CMOS sensors currently on the market can see around 14-16 (such as the Nikon D810 at base ISO 32 or the Sony a7SII/ a7RII). When facing a vivid, colorful sunset, humans can easily see both pretty colors in the clouds as well as details in the backlit shadowy foreground – a very wide dynamic range. The limited dynamic range of cameras compared to our own vision can be extremely frustrating to landscape photographers, many of whom (myself included) strive to capture a natural scene with as much fidelity to reality as possible – we want to create photographs that match what we see in our mind’s eye. This limitation is a factor of an imaging device’s “dynamic range”, which refers to the gap in luminosity between the lightest and darkest parts of an image.
Have you ever noticed when photographing a sunrise or a sunset that your DSLR camera can’t capture the brightest and darkest part of the scene at the same time in one exposure? That you’re forced to choose a single exposure that’s correct for one but not the other?
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