Michael A. Stecker
mike@mstecker.comt

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High Dynamic Range (HDR) Images
http://www.hdrsoft.com/

If you have ever photographed a high contrast scene, you know that even the best exposure will typically have blown out highlights and flat shadows. One way to solve this problem is to take multiple exposures to optimize bright areas (under expose) and dark area (over expose).   One then can combine these images to produce more dynamic range.

The process consists of the following steps:

1. Take two or three photos of same scene: normal, 1 - 2 stops under exposed and/or 1 -2 stops over exposed

2.  Align and merge the images in either Adobe Photoshop CS3 or Photomatrix Pro to produce a radiance HDR (.hdr) 16 or 32 bit composite image

3. Produce a tone mapped image (from step 2) in a program like Photomatrix Pro

Example

original image
Photo taken hand-held with Canon A710IS digital camera at iso 100, aperture priority at f/5.6, evaluative metering and
no exposure compensation

same image, but under exposed 1 f-stop
Photo taken hand-held with Canon A710IS digital camera at iso 100, aperture priority at f/4 (exposure compensation to under expose 1 f-stop), evaluative metering

High Dynamic Range (HDR) tone mapped image
The first two images were combined in Photoshop CS3 to produce a 32-bit .hdr radiance high dynamic range image.
The file was then opened in Photomatrix Pro software where it was tone mapped.