Thursday 18 October 2012

Top of the World with Albert W Stevens

This week's breathtaking freefall from 128 thousand feet by Felix Baumgartner has reminded me of another high-flying pioneer who also plays his part in the history of infrared photography.

Up to 1956 the record for a balloon ascent was held by Albert William Stevens and Orvil Arson Anderson of the Army Air Corps who reached 72,395 feet on November 11 1935 in their sealed gondola named Explorer II. They launched from South Dakota with millions listening on live radio. [Pathé newsreel coverage here.] Stevens and Anderson, together with William Kepner, had made a previous attempt, 1934 in Explorer I over Nebraska, but the balloon burst and the intrepid trio had to parachute to safety from the plunging gondola. There's a good piece about Stevens and the preparations for this ascent in the March 17 1934 Literary Digest. You'll note the photograph of him and a huge aerial camera, for Stevens was an accomplished aerial photographer.

Many of his photos were taken on infrared film, to combat the problems caused by haze when photographing from altitude. He took the first photograph to show the curvature of the earth and he photographed the shadow of the moon on the earth during the 1932 solar eclipse over the US. His images from Explorer II included the highest photograph ever made (a record that also stood until the 1950s) and covering the largest area ever taken with a single lens, showing a horizon around 330 miles away. (The specification was 1/25th second using a Fairchild F4 camera with a Kodak 304mm f5 lens on Eastman infrared Aero film through a red filter.) This wasn't the longest distance Stevens managed to photograph. His 1933 aerial photograph of Mount Shasta in California was taken from a plane flying at 23 thousand feet from a distance of 331.2 miles. The atmospheric haze rendered the mountain invisible, so the camera was oriented using a compass. The Mount Shasta photograph, courtesy of the Kodak Archive in Rochester, was included in the Infrared 100 exhibition.

Stevens's adventures were usually undertaken with the help of the National Geographic Society and stories of his exploits and many of his photographs can be found in editions of that journal from the first half of the 1930s. The Explorer II gondola is now in the US National Air and Space Museum.