Your Light Meter Doesn’t Lie

Eyes may perceive light as even when it's not

By Bruce Barnbaum Back to

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Coutances Cathedral is located in northwest France. Though it is not one of the “storied” cathedrals of France (such as Notre Dame or Amiens) it is a marvelous structure.

I visited the cathedral in 1999 on a 10-day trip through Normandy, prior to presenting a workshop in the south of France. The portion of the soaring structure that resonated with me the most was the east end of the cathedral, its rounded apse. The cylindrical columns holding up the magnificent vaults, as they curved gently around the eastern end was a truly amazing sight.

Fortunately, I had a great deal of experience photographing structures like this, for in 1980 and 1981 I had done a major study of the cathedrals of England. The lighting within these marvelous, ancient cathedrals is extraordinarily deceptive, as I had previously learned. They seem to be bright and evenly illuminated throughout. Yet light meter readings tell a very different story. The light levels are low, except immediately around the windows.

Dealing with uneven light

Furthermore, what often seems like very even lighting throughout the structure is, in fact, quite uneven and quite contrasty: very bright near the windows; quite dark away from them. The low light levels require long exposures, so reciprocity failure effects come into play, which further increases the contrast. For some reason the eye (at least my eye) fails to see these problems. So, having encountered them nearly 20 years earlier in England, I immediately decided to mistrust my own eyes, instead relying on a set of careful meter readings. Sure enough, the light levels were generally low, and the light was remarkably uneven. I would have missed all that if I had relied on my eyes, exclusively. Your eyes can fool you (and mine certainly have on many occasions), so the light meter—the truth teller—can be an extremely valuable tool at those times.

I aimed my 4×5 Linhof Technika camera (with a 75mm lens) straight up from a point between the columns, encompassing enough of the apse to convey the feeling of structural curvature that was so important to me. I also encompassed the full range of light, from the windows high up in the clerestory and their bright light on the nearby vaults, to the far darker walls and lower columns closer to me. I made a 41⁄2 minute exposure on Tri-X film at ƒ/24. I developed the negative with my two-solution compensating development process that I thoroughly discuss in my book The Art of Photography. That allowed me to compress the high contrast range, while maintaining good detail and superb tonal separations throughout.

Printing

It is a wonderful negative, with good densities from the high- lights to the deepest shadows. Yet the straight print shows the problem: the negative is still too contrasty. But it’s easily within the realm of any good variable-contrast paper. I lower the contrast from that of the straight print by dialing in 25 units of yellow filtration on my LPL dichroic enlarger.

During the basic exposure of 25 seconds, I dodge the center portion of all columns, thus smoothing out the sharp tonal break between the upper columns, lit strongly by the windows high above, and the lower portion of the columns. The dodging yields a more gradual tonal transition, which is more in keeping with my feelings of the cathedral.

Then, following the basic exposure I reduce the contrast level further by dialing the yellow filtration to 85 units, burning the upper vaults for 21⁄2 minutes. During that time, I move a card with a small hole around the bright areas to be burned—while gradually changing both the size and shape of that opening with a second L- shaped card (a technique also fully dis- cussed in my book)—for the entire 21⁄2 minutes. Beyond that, this image requires no bleaching, so I’m done.

But the print has a luminosity that I feel conveys the essence of the cathedral. Though there was a great deal of contrast within the structure, my eyes didn’t see it that way, and I didn’t feel it that way. To me, it felt bright everywhere (which is one of the great accomplishments of medieval ecclesiastical architecture), and I wanted to convey that feeling of soft, diffused light.

I’ve printed it on Forte Polygrade paper, in sizes up to 30×40 inches (for a recent exhibit at the Benham Gallery in Seattle). It’s wonderfully sharp, and it holds up magnificently to that size.

But I did have another problem to deal with: which way should I turn the photograph? Since the camera is aimed straight upwards I can turn the image any way I want. The straight print is published here in a horizontal orientation; the final print as a vertical. Obviously there are two more possible orientations, but neither of them seemed right to me. (My wife prefers the horizontal orientation of the straight print; I prefer the vertical. I get more votes on this issue.)

So why do I choose the vertical? To me, it’s a simple choice. I find it a much more dynamic way of presenting the image. It accentuates the height of the columns, creating a feeling of reaching to the heavens and to the brightness of the vaults high above. That, of course, does not make it the best choice, but it certainly makes it my choice.

I’ve often thought that for images like this I should sign the print at all four corners, and let the buyer make the final decision. Maybe that’s the best solution.


About the Author

Bruce Barnbaum
BBarnbaum
Bruce Barnbaum teaches photography workshops throughout the year, focusing on the art of seeing and the art of conveying impressions of your photographed world (real or imagined). He has two monographs in print: Tone Poems - Book 1, 2002; and Tone Poems - Book 2, 2005. Both are collaborative efforts, featuring a CD of classical piano music performed by Judith Cohen. www.barnbaum.com