High Dynamic Range (HDR)
HDR Pro is another tool in Photoshop CS5 that allows you to com-
bine information from multiple frames to create something you
can’t capture in a single shutter click. HDR stands for high dynamic
range, meaning that the results capture both ends of the shadow-to-
highlight continuum. HDR Pro lets you combine multiple frames of
the same subject shot at different exposures, which allows a wider
range of luminance information to be combined into one image.
So instead of just exposing for either shadow or highlight, you
can shoot a succession of images that capture both. The result is
a compilation that in some ways more closely mimics the way our
eyes—rather than our camera sensors —are able to take in a broad
range of light information.
On a practical level, HDR Pro, which has been vastly improved in
this version of Photoshop, works similarly to Photomerge. First, you
shoot a set of photographs at various exposure stops (preferably
with a tripod, and varying in either shutter speed or ISO). Then you
point Photoshop at that collection and the magical calculations go to
work creating a single image. The new HDR Pro feature in CS5 then
allows you to assert all kinds of creative control over that output.- Select eight images that represent a wide range of
exposure settings. For this exercise, we’ll use a se-
ries of photos I took with an Olympus E-30 in Steam-
boat Springs, Colorado. I shot them from the dark interior of a
ramshackle barn, looking out through cracks in the walls and
door into bright sun reflecting off a snowy landscape. I used a
tripod and an identical aperture setting for each shot, simply
varying the shutter speed to create different exposures. On one
end of the luminance range, an exposure with a shutter speed
of 0.5 seconds captures highlight detail without blowing out
completely (although there are spectral highlights); on the other
end, an exposure of 20 seconds is enough exposure to record
the texture of the old wood in the dark recesses of the interior.
If the Mini Bridge isn’t still open from the last exercise, choose
File→Browse in Mini Bridge. The Lesson 09 folder should still
be available in your Recent Folders pane. Click Lesson 09, and
then double-click the HDR Exposures folder in the Content
panel. Finally, open the DNG subfolder by double-clicking it.
Click Exposure 0.5 sec.dng and then scroll down the Content
panel and Shift-click the Exposure 20.0 sec.dng file, thus grab-
bing all the images in between, as I’ve done in Figure 9-35.
Figure 9-35.
328 Lesson 9: Pro Photography Tools