Determining the Shooting Location
In typcial re-shoot photography, a photographer can compare the original photo to the camera’s viewfinder and continually shift the camera to obtain a similar view. Because our camera was hanging from a kite, we did not have the luxury of looking through the viewfinder and comparing the view to Lawrence’s photograph. Instead, we had to rely on computer software to pinpoint the exact location before going out to do the shoot.
Although it is possible to determine exactly where George Lawrence positioned his camera 100 years ago, it would not be sufficient because we were not using the same camera and lens. George Lawrence shot the photo using a 19 inch lens and a huge, 22” x ~55” negative, which yielded a field of view of approximately 145°. We took the contemporary photo using two different cameras:
- Hasselblad XPan II 35mm film-based panoramic camera with a 30mm lens (94° horizontal FOV)
- Nikon D70s 6-megapixel digital SLR camera with a 10.5mm fisheye lens (138° horizontal FOV)
One of the defining characteristics of Lawrence’s photo is that his camera was positioned so that the viewer can look past the Ferry Building, straight down Market St. Our aim was to position the camera in this same line of site. While it’s fairly straightforward to key in GPS coordinates and position the boat on top of the shooting location, we had the additional challenge of estimating the camera’s location, which was several hundred feet from the boat. Malcolm Johnston, USGS scientist and boat captain, did a marvelous job of putting the camera in the correct location.
Map showing the optimal shooting locations for both cameras. A red line is drawn over Market St. and shows the ideal vantage point for positioning the cameras. Based on the field of view of each lens (Hasselblad: 94°, blue line; Nikon: 138°, green line), we can determine the optimal point to position the cameras so that we capture the entire peninsula and look down Market St., just like Lawrence did 100 years ago.
Utilizing a software tool called ArcScene from ESRI, we were able to determine the height at which Lawrence snapped his photo. We loaded a digital elevation model (DEM) of San Francisco, and positioned the model in a similar vantage point to Lawrence’s photo. Specifically, we used a hill in the distance that is visible in both the model and Lawrence’s photo. By placing the Pacific Ocean in the same relative position in the computer model, we can obtain a similar vantage point. Then it’s simply a matter of asking the software how high that vantage point is.
We determined that Lawrence’s camera was positioned approximately 290 meters (950 feet) above San Francisco Bay. This is much lower than 2,000 feet, as documented by George Lawrence.
One of the biggest challenges would be getting the camera high enough. Lawrence did not have to concern himself with FAA regulations or air traffic in 1906. With two international airports nearby, we made the decision not to fly the kite over 500 feet to avoid any potential problems. Because the kite flies at varying angles and the camera was attached to the kite line 50-100 feet below the kite, it is estimated that our shots were taken between 300-350 feet high.