In the clear light of a November day I strode up the Virgin River in Zion National Park, Utah. The water down the Virgin Narrows ran fast and cold, and my feet—in heavy hiking boots and two sets of wool socks—were wet but not too cold. My main concern was keeping the camera equipment on my back dry considering the wet conditions. One slip on an underwater rock and all the electronics would be toast.

I struggled up the Narrows, making my way through chambers carved from naked rock, vast cathedrals of nature that suddenly opened, and poetic intimate passages where the river hugged the rock and sunlight filtered down from the plateau far above.

A couple of miles up, the afternoon sun of the shortened autumnal day backlit the tree shown up the cliffside in this photo. In the fast-flowing water of this stretch there was no place to put my tripod down, so I boosted my ISO slightly (to 320) and fired a frame. Then the lighting was gone and the world of the Narrows turned to shadow.

I would have been surprised, but not astonished, had I fast-forwarded a few years to today and seen this image in black and white as I processed it last night. Although it looks good in color too, the essential elements have to do with contrast in lighting between the strong light behind the tree and the very dark sculpture of the cliff wall elsewhere.

You can find more of my thoughts about monochromatic vision and digital conversion techniques in the replay of my webcast Black & White Digital Photography (the video is a bit more than an hour), and in my book Creative Black & White: Digital Photography Tips & Techniques.

Exposure data: 56mm, 1/60 of a second at f/5.6 and ISO 320, hand held.