March 01, 2011 — High dynamic range (HDR) imaging became mired in controversy when it appeared a few years ago, much as color photography did when it first appeared, or photography itself did when the technology became possible. But HDR, like the others, is simply a tool that is available if you choose to use it.
Nik Software has given digital photographers who see the world with an HDR vision a valuable tool to work with. Nik HDR Efex Pro incorporates four tone-mapping algorithms, whereas most other HDR programs include only one or two. In addition, it includes a wide range of presets that in many cases may be all you need to produce a final image. If not, there is a substantial set of adjustments available to customize the look of your image, including Nik’s proprietary U Point® technology that allows you to apply many adjustments to specific areas of the image.
HDR Efex Pro installs as a plug-in for 64-bit Adobe® Photoshop® CS4 and CS5, or as a 32-bit or 64-bit plug-in for Lightroom® 2.6 (or later) or Apple® Aperture™ 2.1.4 (or later). While Nik doesn’t recommend it, I’ve found it runs successfully, if somewhat slowly, in 32-bit Windows XP. Nik recommends 4GB of RAM, which is one reason for the 64-bit OS. When creating the 32-bit HDR original for HDR Efex Pro from a camera’s high resolution RAW files, the more RAM the better.
While HDR Efex Pro is available on your computer as a stand-alone application, it is best to access it through File>Automate menu in Photoshop or the Tools menu in Bridge. When you use either of these methods a dialog box opens that gives you several options. These include the ability to have HDR Efex Pro automatically align the images (always a good idea with multiple images), open the HDR image as a Smart Object, and choose whether or not to have the program attempt to eliminate ghosting artifacts. The HDR Efex Pro multiple image Merge dialog is compatible with all 8- or 16-bit or RAW file formats supported by Photoshop.
Using the Lightroom or Aperture route bypasses this dialog box. However, if your images are overly noisy or suffer from extensive color fringing or need other pre-HDR corrections, then using Lightroom or Aperture may be a better option. Nik has left the decision to you.
Once HDR Efex Pro has done the preliminary processing and aligning of the images, the HDR image opens in a large preview window in the center of the screen. It is repeated as a thumbnail 33 times in the Preview Browser in the panel on the left of the interface. Each of the 33 thumbnails shows how the image would look if processed with one of the preset looks.
The default look has no additional adjustments applied to it. As you scroll down the Preview Browser you can click on a preset that you like and the software immediately applies it to the image in the central preview window. The presets range from the photorealistic default to the surreal, to several that offer monochrome and toned looks. If you didn’t know where you wanted to go with the image, HDR Efex Pro shows you a range of possibilities. For some images you might be happy with the result using a preset and simply click ‘Apply.’ HDR Efex Pro processes the image and sends it back to Photoshop.
If you decide to work on the HDR image further, the right palette of the interface contains an array of adjustment sliders. If you watch them as you click through the presets in the Preview Browser, you can see how they adjust for each preset.
The Tone Compression slider at the top of the panel, set off by itself, controls the dynamic range of the image. This is the most important control in HDR imaging. Moving the Tone Compression slider to the right decreases dynamic range, lightening dark values and darkening light values while leaving a full range of tonality and color. Moving to the left has the opposite effect.
Grouped below the Tone Compression slider are nine controls that provide Global Adjustments to the image. With any preset other than the default that is active for the image, the pointer on each slider may or may not be in the default central position. These include exposure, contrast, saturation, structure, blacks, whites, warmth and HDR Method, and Method strength. Each functions over a wide range of values. If you create a combination that you feel you would want to use in the future, you can save it, along with any Finishing Adjustments like a vignette or a curves adjustment as a new preset. It is also possible to import and export presets.
The HDR Method drop-down menu in the Global Adjustments is worth investigating for every image. Each of its 20 options interacts differently with the color and detail of the image. Used in conjunction with the Method Strength slider they provide an even wider range of image customizing possibilities.
Below the Global Adjustments group is Nik Software’s U Point® tool for setting Control Points. You use Control Points to make local adjustments in the image. All of the Global Adjustment options other than HDR Method are available, including Method Strength. The only tool I miss in both the Global Adjustments and in the Control Point options is a way to adjust the RGB values.
When you are happy with your global and local adjustments, the next panel down contains the finishing Adjustments for adding a vignette or making a final tweak to the levels and curves. Unfortunately there are no RGB readouts anywhere in the interface and the histogram at the very bottom of the panel is pretty useless, so you don’t have a precise idea of what is going on with RGB values. However, if you set the options in the Settings to save the HDR image as a 16-bit file in Photoshop, you have the Photoshop controls when you click the ‘Apply’ button to accept your adjustments and return to your host application. If you selected to run the image in HDR Efex Pro as a Smart Object, it is saved as a 32-bit TIFF or PSD file that you can access later through HDR Efex Pro for further adjustment.
HDR Efex Pro provides you with all of the tools you need to create believable photorealistic images that approximate the brightness range that you saw in the original scene or to create wildly artistic interpretations of the scene. The ability to create monochrome and toned images is an added bonus. The final result depends on your vision and your taste.
The suggested retail price of HDR Efex Pro is $159.95. A 15-day demo version is available from Nik Software at www.niksoftware.com.
Stan Sholik is a commercial/advertising photographer in Santa Ana, CA, specializing in still life and macro photography. He is currently working on a book about Nik HDR Efex Pro to be published by Wiley Publishing.