The previous blog presented an impossible task for any camera—record a dark interior subject against a bright window. This high dynamic range experiment could not be recorded in a single exposure. HDR processing of several bracketed exposures is one approach for dealing with such high contrast subjects. But there are other options.
An alternative method would be to use Photoshop layers and masking to blend the properly exposed areas of the bracketed photos. This approach provides better control over the final result. HDR processing can look artificial and may not provide the best possible blend of the bracketed photos.
Consider these exposures of the same window shot—one for the interior foreground and one for the sunlit exterior. The two photos stacked in Photoshop layers can be blended to combine the best sections of each. The process involves careful masking and accurate selection techniques which is more labor intensive than HDR processing, but the results can be well worth the effort.
In the case of these photos, the line between the properly exposed areas is sharply delineated and easy to define. Where there is a more gradual shift between light or dark areas and properly exposed sections, the layer mask can use gradation tools, soft edge brushes or feathering to create a smooth transition. This process offers unlimited adjustments and total control over the final result.
The layered blend of bracketed exposures closely resembles what the human eye perceives. It is more natural looking and not obviously processed as an HDR tonemap might be. When it comes to high dynamic range subjects, you have a choice of methods for blending bracketed exposures. HDR software such as Photomatix does a great job with most subjects. But the use of layers and masking in Photoshop is another approach that offers greater control and perhaps a bit more creativity. The choice is yours. To learn more about masking and blending check out this YouTube tutorial from Lynda.com.
Of course if you are going to blend two or more exposures of the same subject, they must be in perfect registration. Alignment can be done in Photoshop, but it is better to start out with photos that are properly aligned. Here a tripod or a pocket size alternative like HandlePod becomes very useful not only for keeping the photos aligned but also to eliminate camera shake in low light.