Exposure Blending - Part 1

I selected this scene because it was difficult. Not because I had to step from rock to rock with camera around neck and tripod across back to get to the other side of this creek. But because the dynamic range of lighting far exceeds what any photographic medium can handle, including film. Plus I wanted the reflections. And it’s a bit of a mind bender. How deep you think that water is?

In the old days I would have used Ansel Adams zone system technique. Yes, most if not all of Ansel Adams’ famous B&Ws where not straight from the camera to print, but in fact where the result of a system whereby dynamic range of lighting of a scene was either compressed or stretched with a combination of negative exposure and development times.

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The photo above is the result of several exposures combined to preserve the details in both the low light and high light areas. The shots below show the dilemma one faces when trying to capture details in either the low light or high light sections with a single exposure. Unlike that wonderful combination of the human eye and brain, the camera cannot capture detail on one end of the luminosity without loosing it on the other end. No photo processing software can do anything about empty or overflowing photon buckets.

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Free Digital Photo Processing Software

There are many great digital photo processing software packages available, many free but limited or only trial ware, others full feature but expensive with a never ending need to buy upgrades. There’s help however, Gimp.

Gimp is an open source photo processing package with features rivaling advanced commercial packages, yet it doesn’t cost a penny and doesn’t have any strings nor nagware attached. Really, absolutely, no kidding! Hard to believe? Welcome to the world of open source, the engine of the internet and many other things.

Start by visiting the official gimp website. Familiarize yourself with what gimp is all about. Installing gimp is pretty straightforward. Download the latest version here. Don’t forget any plugins you may want, installed after you install gimp. Snoop around and see if there are any you may want. Note that you don’t need any plugins to use gimp, as it will pretty much be able to manipulate any non-proprietary file format such as jpeg, png, bmp, tiff, etc. just with the basic install. If you want to work directly with raw files such as Canon cr2, you will need to install the UFraw converter plugin. Install gimp first and then the plugin. During the install I wouldn’t allow UFraw to take over the file associations (uncheck them all).

After you install gimp and UFraw, open gimp, then open your file form the file menu. UFrwaw will then open the file for you. At this point you can do some manipulations (UFraw is a essentially a standalone processing package by itself), but I wouldn’t. Instead just click on the ‘OK’ in the lower right corner, and you’ll be taken to the gimp program.

You might want to use gimp without UFraw first to learn a bit about gimp (without the raw converter) by right clicking on a graphics file (jpeg for example) and then ‘open with’ gimp. For detailed help on using gimp, google is your friend.

Happy processing.