Taming the Extreme Exposure Values of Landscape Photography

With all this snow lately, it’s hard to imagine that warm weather is just around the corner. The days are getting longer with great light in the early morning and beautiful long shadows in the evening. Those are the best time to capture landscapes with a three dimensional quality to them. The only stumbling block we have in recording these scenes is the tremendous exposure differences that exist between the sky and the terrain below. Automatic exposure on your camera won’t do it. Either the sky will be exposed properly and the ground will be too dark or alternatively the ground will be recorded properly and the sky will be white. The range is just too much for film or the digital sensor to record with one exposure value. There are two techniques you can use to handle this extreme lighting situation.

Firstly, you can use graduated neutral density filters to even out the exposure. The filters are darker on top and that fades to a clear filter on the lower half.

Made by Cokin or Singh Ray, they are rectangular shaped filters 84 mm wide that fit into holders that have three sets of slots so you could stack up to three different filters at a time. The purpose of the graduated neutral density filter is to balance the intensity of the exposure from the sky with the light on the ground area. The reason for a rectangular filter is to give you the ability to slide the filter up or down in the holder to line up the filter’s density change with the horizon so the filter effect will look natural. Graduated filters are available in neutral gray tones or in different shades such as blue, tobacco, red, etc. for different effects.

Another method to equalize the exposure difference involves digital Raw files and a process referred to in Photoshop as “merging to HDR”.

In simple terms, you set your camera up on a tripod, select Raw as your file format, and compose your image. Keeping your aperture fixed to maintain the same depth of field and varying your shutter speed, shoot one image with the correct sky exposure, another shot with correct shadow exposure, and about three or four shots with different exposures between the first two. You now have a full range of exposures from highest to lowest values in the scene. When you merge these images through the HDR process, the final image that emerges will have proper highlight detail as well as shadow detail and everything in between. It’s a great process and can create images that are not possible through normal means. Raw files are available using any dSLR camera and a few higher end compact digitals such as the Canon G10.

The HDR process is available with Photoshop but there are several dedicated software programs such as Photomatix that also create excellent images under extreme lighting conditions.