Imagine a dark interior with objects in front of a bright window at midday. The human eye can see detail in the objects as well as the sunlit scene behind it. But it is impossible to take a photograph of the scene that reveals as much detail as the eye perceives. Film couldn’t do it and neither can the sensors in today’s digital cameras. Human eyes have a dynamic range that far exceeds the capability of the most sophisticated electronic sensor.
HDR Processing Software
Fortunately, the electronic age has given us a choice of workarounds to deal with high dynamic range subjects that far exceeds the bygone darkroom gymnastics of dodging and burning in the film days. A common solution is HDR processing of three or more bracketed exposures using software such as Photomatix. It works quite well and the results can be spectacular. This software is often the first choice for dealing with high dynamic range subjects.
But understand that HDR software processes the entire image at once. It provides a mind boggling choice of presets and sliders to adjust contrast, saturation and so on. Control over specific areas of the image is not available. Ultimately you have to work with what the software delivers. This can be a very natural and pleasing representation, exactly what you had in mind. Or it can be a highly processed, over saturated tonemap that screams HDR. The image at right is a blend of five exposures. It did a fair job of combining the dark interior and bright outdoors but it is not perfect.
Use Photoshop Layers to Blend Images
Better control over the final result can be achieved with layering and masking techniques available in Photoshop. This is a more technical and labor intensive procedure than HDR processing. But it does give you ultimate control over every element of the image, rather than leaving manipulation to the workings of an algorithm. This informative tutorial from Digital Photo Mentor provides an excellent overview of masking and layering techniques in Photoshop. These methods involve the combination of several exposures. While the software can align the photos, it is best to provide camera stabilization to guarantee perfect registration of all photos.
Improve Tonal Range in Lightroom
The image processing capabilities of programs such as Photoshop and Lightroom can deal with high dynamic range subjects in a single image rather than a series of bracketed exposures. This approach works best if you keep a couple of factors in mind. Be careful not to over expose the highlights. It is not possible to pull detail out of over exposed whites and information in that area is usually not recoverable. If the plan is to process a single image to reveal a full tonal range, it is best to shoot in RAW. This preserves a more complete range of tonality that can later be brought up with adjustments in your chosen software. Even the most obviously under exposed image can be manipulated to bring out an astounding tonal range that would have been impossible to recover in the age of film. This informative tutorial demonstrates what can be done in Lightroom with seriously dark areas of a RAW photograph.