BS Photography.

Mastering HDR Photography.

The human eye is amazing. It can see a scene in its entirety without losing detail due to variations in lighting, such as a strong backlight. The camera on the other hand will be unable to capture both detail in the backlight and the foreground subject. Part will be either overexposed, or another part underexposed.

As you can see, in the first photo, the barn is exposed well, but the sky is completely blown out, while in the second shot, the sky shows detail, but the barn and foreground are too dark, or underexposed.

There is an easy way to get detail everywhere, and my technique of choice is called HDR. For those of you that care, HDR stands for High Dynamic Range. Dynamic Range is the range of brightness that a camera can detect.

HDR broadens this dynamic range by combining photos of different brightnesses and finding the best exposure values from each photo, and with my program of choice, Photomatix, the image is created from your source images automatically, save for some tweaks to your taste.

Okay, enough background, let’s get to how to do it.

The first thing to do is take the photos. Using a tripod, compose your scene and bracket the scene. Underexpose the scene for detail in the bright area, overexpose it for detail in the shadows, and shoot a shot or 8 in between. Usually I just shoot one or two in between. Use the camera’s short timer, one or two second, so it will not move as you press the shutter button. It’s obvious that when you stack photos, they should line up well.

We’ll use the barn as the example.

I like to use variations in shutter speed, but you can vary the aperture too, or both.

Now that you have your source images, get to your computer and fire up Photomatix.

In the main Photomatix window, select Generate under the HDR menu, select your source images and click OK. You’ll then see another window with the options align source images, attempt to remove ghosting artifacts, etc. Leave the options as default to start, if you used a steady enough tripod and a self timer or remote, you probably don’t need to align the source images, and if there was cloud movement, I would recommend not aligning source images because the program may use moving clouds as reference points and mess up the overall alignment.

Click OK and wait, an image will appear, but you will not see the tones you want to, but all the data needed is there.

Now click Tonemapping, under the HDR drop down, and play around with the sliders and such until you get a satisfactory result, and then click apply. Save your image, then open it up in another image editor, such as GIMP, Photoshop, or Fireworks and do the finishing touches such as crop, levels adjustments, burning and dodging, watermarks, cloning, etc. Save that, and share/print/admire your completed image!

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Alternatively to bracketing your shots, you can shoot in RAW format (if your camera supports it)

After getting your RAW files to the computer, select “Single File Conversion” from under the Automate menu in Photomatix, select the check box, “Convert RAW file or 16-bit Linear TIFF file to HDR Radiance RGBe”

In the file browser navigate to your RAW file(s) that you want to convert to HDR, select them, and run the batch. Then find those files and open them in Photomatix, skipping the “generate HDR” process.
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Some compact digital cameras are modifiable to shoot in RAW through the CHDK firmware modification available here. I would be interested in those results if you would send me links to them. (I shoot in RAW with my Digital SLR camera, my Compact Digital does not support this mod)