Scenario 4: metering a different high-contrast scene

Here's another problem child:

As with Fig 7, this scene as a whole averages out to something brighter than middle grey. There is no convenient green lawn to meter off. Worse still, the clouds are extremely bright. The truth is that I naively trusted the evaluative meter mode of my camera when I exposed this frame. As you can see, it chose to sacrifice much of the cloud area to over-exposure in order to keep optimum exposure in the rest of the scene. There was a light breeze, so combining bracketed exposures was not an option.

What I should have done would have been to either

• Use the centre-weighted meter mode of my camera then apply one stop of exposure compensation (which direction?) to try for a good over-all exposure (same as evaluative), then take a second frame at two stops compensation to try to bring the clouds under control.
• Use a spot meter and apply the spot metering recipe.

Let's walk through the full spot meter recipe using this frame as an example. Ideally, I'd like to retain detail in even the most glaring portion of the clouds without losing my shadows. The brightest portion of the clouds meters in at 1/2000^th. The shadows meter in at 1/15^th. That's 8 stops. If I'm using neg film, that's quite do-able: I expose halfway between the two extremes at 1/125^th (centre-weighted wins again). If I'm using digital JPEG or slide film, this scene would be a good candidate for ND grad filters. Otherwise, I kiss the glaring clouds good-bye and use the slide film recipe: i.e., subtract 2½ stops from 1/1000^th for my exposure. If I'm shooting digital raw, depending on my camera I have 7½ to 8 stops, so again my best bet is to use the slide film recipe.

However, there is yet another interesting feature to this frame. The sun is over my right shoulder. When you have specular glare and the sun is either to your left or right (not straight ahead or straight behind), you can use a polarizer to cut down on the glare.

Law of Metering

Dale's Law of Metering: the amount of time you have to meter a scene is inversely proportional to the value of the shot. Or: beauty and behaviour are equally fleeting.

In other words: there is rarely enough time to think through the problem at hand. Your only hope is to know your chosen tools so well and to practice using them so much that your automatic reactions will be spot-on.

Final Exam

How would you meter this dawn-over-fen scene? There is no breeze but the sun is rising steadily and the clouds are not holding still. Assume you have 30 seconds to work in; assume you are using your current equipment:

In fact, to get this shot my tripod and I teetered on a sharp, muddy slope at water's edge, surrounded by dense branches, and swarmed by mosquitoes ... so maybe 30 seconds is over-generous. ;) What would you do, assuming 5 seconds?

Further Reading

The second editions of The Camera and The Negative by Ansel Adams, after more than half a century, remain the keystone of photography. While their primary focus is black & white film photography, most of the concepts apply to colour and digital. These books are clear and simply written – a joy to read.

• Quick, Accurate High Contrast Exposures for Digital Cameras
• The Case of the Mistaken Multi-Meter
• Exposure on DPFWIW
• Understanding Exposure by Michael Reichmann
• Zone System Wikipedia article
• A Simplified Zone System for Making Good Exposures by Norman Koren
• Dynamic Range by Jerry Lodriguss