Lunch on a skyscraper: The history of a famous photograph

This is the original glass-plate negative of the iconic photo of construction workers eating lunch on a girder during the construction of Rockefeller Center's RCA building in 1932.

Today, those of us who remember using analog cameras remember taking photographs on film — literally a plastic (or, earlier, paper or celluloid) strip covered with a film of light-sensitive chemicals. But once upon a time, when you took a photograph, you took it on a piece of glass. The glass could be as small as 3 inches by 5 inches, or as big as 11" x 17". Originally, each piece of glass had to be dipped into an emulsion of chemicals on site, and the photograph taken before the chemicals had dried — a time on the order of minutes. That meant that, wherever photographers went, they had to carry an entire darkroom with them.

George Eastman is credited with inventing film in 1884, but the type of glass negative you see above was an important in-between step, linking the cumbersome wet-plate process and the infinitely more convenient world of film. Instead of a bath of chemicals, it used a gelatin — with chemicals suspended inside like the bits of pear in a jell-o salad. Gelatin glass plates didn't need a portable darkroom. And they could capture an incredible level of detail. According to the Dayton History Center, you can read the writing on tiny signs in the background of some of these shots.

The downside: Taking a photo with these plates required exposure times that would seem incredibly long to us today. For instance, a basic film photographer just working with a point and shoot camera might use a film speed of 400 ISO. According to an artist working with glass plate photography today, that process produces an equivalent "film speed" of about 1/2 an ISO — two whole seconds to get an exposure on a nice, sunny day outdoors. That doesn't sound long, but it can be an eternity if you're trying to capture a spontaneous moment, like one guy lighting another's cigarette.

This is part of why we know that the famous photo of construction workers on a girder was actually a staged shot. That ... and the fact that there are other much-more-clearly staged shots from the same sequence of photos. At the New York Times Lens blog, you can see those photographs, and learn more about the history of an iconic New York scene.


  1. “This is part of why we know that the famous photo of construction workers on a girder was actually a staged shot. That … and the fact that there are other much-more-clearly staged shots from the same sequence of photos.”

    Were all the photos on the NY Times blog entry taken with the same long exposure? I don’t know how you would hold the flapping flags in photos 3 and 6 still for 2 seconds.

    1. Reading further into the note about film speed, that’s two seconds at f16.  Change to f2 and you’re at 1/8 a second.  The shooter might have done some extra work during the developing process to get another stop, possibly two.  Now we’re talking about 1/30th of a second.

      However, all of this is moot since the author also concedes ” the slow speed of 1/2 ISO is very close to what emulsions were in the 1870′s.”  I have to imagine that sixty years after that they had techniques that allowed for faster work, 1931 gave us Harold Edgerton and the first stop motion photography.

  2. I didn’t get the chance to see that particular glass negative, but I did have the opportunity – years ago – to visit Corbis’s storage facility for that and a *lot* of other negatives (including many of the original glass plates with Lincoln’s portraits).  Its buried away deep underground in an old granite mine (IIRC) in Northwestern Pennsylvania.  A number of Federal agencies have storage facilities there too, along with the World Bank and ESPN and Disney.  Naturally, its out of the way and well-guarded – but the benefits of a nice dry, climate-controlled facility (with reliable energy) make it an ideal location for storing the sensitive negatives. 

  3. Nice overview of early photography. Back when I was a very young, budding photographer, I used to have to ask the dinosaurs to hold certain poses for 10 or even 20 seconds to get the right shot. Photographic images were made on huge slabs of lava rock and were developed in dark prehistoric caves. Aah, those were the days…! Digital is so much easier, isn’t it?

      1. Every shooter had their own various combinations of roots and berries.  These were tightly kept secrets, handed down from father to son.  Eventually, families rich in heritage and steeped in tradition would merge and recipes would be shared between clans, making the whole stronger than the two original parts.  Many were to perish through the years, but Olan and Mills maintained strength through cunning and skill eventually joining forces to defeat the mighty Sears family of portrait photographers.

  4. It isn’t “two whole seconds” to get an image on a sunny day. With a lens aperture of f/4 (possible with some plate cameras of the day), an exposure of 1/8 of a second would be about right. Still not easy, but possible.

  5. I’m not normally afraid of heights, but every time I see that famous photo, I feel just a little woozie, and am struck again by how brave, macho, and maybe a little foolhardy you had to be to work construction then on skyscrapers.

    The subjects in the photo look so ‘just-another-day-at-the-office’.

  6.  Photography was quite advanced by 1930 and amateurs had been taking many fine images with hand held cameras (requiring short exposure times) since 1900 or so.  The numbers quoted above for exposure times sound very far fetched.  I can’t imagine a reason the chemistry on glass would be any slower than on regular film.

    1. The chemistry was significantly different, and much less controlled than on modern films – also, the numbers are from home made plates. So, while reasonable in the very specific case of the photographer in the alternative photography link, plates of the time were often faster than this.

  7. This article could really have been better researched. The linked piece on dry plate work is good, but higher speeds can be achieved, and were. A lot rests on how the age of the emulsion, how quickly it was mixed, the colour of the light used (less sensitivity to yellows often), whether is was made in a factory with tight controls on these things etc. etc.

    So likely the film was of a much higher speed, maybe around 4 is likely I think? With that speed, and a wider aperture of 5.6, then the shutter speed on a sunny day comes to 1/30. Much more manageable.

    That is conservative, I think. Glass plates were often factory produced then, allowing for much greater speed and consistency between plates.

  8.  “That meant that, wherever photographers went, they had to carry an entire darkroom with them.”

    Not exactly. They weren’t developing the prints on site, so they did not need an “entire darkroom”. I agree with the above commenter, this article could have been better researched.

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