Do a quick search on Flickr or Google for “HDR” and you’ll see photos that are truly amazing: full of contrast, intensity, depth, and detail. High dynamic range (HDR) images have bold shadows and brilliant highlights that most typical photos don’t have. They are created by merging multiple exposures, giving you the best from each on a single image.

This photo by Flickr user Paolo Margari is a gorgeous example of high dynamic range.

You don’t need a high-end camera to produce HDR images. A fairly basic digital camera (one where you can adjust the exposure compensation or f-stop), a sturdy tripod, and a copy of Photoshop CS2 or CS3 will do the job. Here’s how, as demonstrated with a rather banal bowl of oranges:

1) The hardest part is getting started. Set up your camera on that sturdy tripod I mentioned. Be sure that you’re able to change your settings without the camera moving around too much. Photoshop can help align the frames later, but for the best results you need frames with hardly any movement between them.

2) Take a series of photos at different exposures (using different f-stops or exposure compensation). Three exposures are usually plenty, or try five if you like. Keep the exposures pretty far apart, taking a shot that’s very dark, a shot that’s very bright, and one right in the middle (normal exposure). Really take the extremes (almost black, almost white) if your camera allows you to do that—unfortunately mine doesn’t, but I took shots as dark and bright as I was able.

Thumbnails of the five photos I took. Some have good highlights, some have good shadows, some have good midtones, but none have it all in one shot.

3) Import your photos to your computer, but don’t open them up your usual way in Photoshop. Instead, go to File > Automate > Merge to HDR. That’s right—Photoshop totally automates the task of merging your images into your high dynamic range shot. Browse to the photos you’d like to merge, and check the “Attempt to Automatically Align Source Images” box which will help compensate for slight movement in your shots. Larger movements will still be noticeable in the final piece with or without this box checked. Click OK and site back while your HDR image is generated. (If you’re the curious type, watch your History panel and Layers panel to see how Photoshop does its magic.)

4) When done, you’ll be presented with a gigantic dialog showing your source files and your almost-finished image. You have the opportunity to change its histogram. My result was a little too blown out, so I moved the slider to the right a bit. Click OK, and your final image will be generated.

Be patient—for really huge files, the merging process can take awhile.

5) Take a moment to compare your final HDR image to the “normal” exposure of your source files. You should be able to clearly see the added highlights and shadows, giving you a more striking result.

The “normal” exposure (top) just doesn’t have the depth of the HDR version (bottom).

6) Finally, you’ll probably want to output your file for print or the web. The merged HDR image that Photoshop creates is in 32-bit mode, and you’ll likely need an 8 or 16-bit file. Go to Image > Mode to make this change, then make any adjustments you like in the HDR Conversion dialog that appears.

This technique can be used in any type of photography, but it produces the most impressive results on landscapes, showing off tons of detail. HDR should not be confused with high definition or high resolution, but the level of detail and intensity can often mimic that of other high-end techniques.

This entry was posted on Friday, August 3rd, 2007 at 1:20 pm and is filed under Photography. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.