Carl Zeiss Walking on the Moon With Armstrong

Zeiss Lenses Celebrate Their Part In The Apollo Moon Landing in 1969

Jul 23, 2009

Many people are remembering the 40th anniversary of man's first visit to the moon and their contributions to the achievement. Neil Armstrong took first lunar pictures.

Some were large, and others smaller, but in such a complex undertaking all played an important part in the overall success of the mission.

In such a journey into the unknown, many factors are literally out of this world. Many things taken for granted on our balmy blue planet take on a different perspective in the harsh environment of outer space.

Aspiring NASA astronaut Walter Schirra to a Houston camera store to buy a camera and ended up with a Hasselblad equipped with a Carl Zeiss lens. In October 1962, Schirra took the camera along on a Mercury space flight and pleased with the pictures, NASA decided on this combination as basis for a camera to take to the moon.

While the camera worked fine inside the Mercury space capsule, the requirements for the moon included taking it outside in the most trying conditions, over 120° C in the sun, and minus 65° C in the shade. Then there is the lack of gravity and a myriad of unknown hazards.

Pioneering Hazards

The Titanic was the fastest and safest passenger liner on the North Atlantic run only the designers did not fully understand the properties of steel at the freezing temperatures of the Atlantic Ocean. When the ship struck the iceberg the steel hull shattered* instead of bending, creating a far larger hole than the designers anticipated.

Another pioneering disaster was the De Havilland Comet*, the world’s first jet airliner. It flew faster and higher than any airliner before, placing new levels of stress on the metal body of the airplane resulting in a series of mysterious crashes. Extensive testing and research revealed the potential problems of metal fatigue that lead to the crashes.

While the failure of camera might not be a threat to the astronauts, Carl Zeiss tried to consider any possible problems raised by the unusual operating environment before Apollo 11 left for the moon.

Refraction In A Vacuum

Refraction is when light bends as it goes between substances of different densities, and the amount of refraction depends on the difference in densities between the two substances. Normally in a lens, the two substances are air and glass. The lens designers tested difference in refraction when it is a glass to vacuum transition so the Carl Ziess lenses still produced the highest image quality.

Compound Lens Cement

A part of modern lens design is the creation of compound lenses, where glass lens elements are cemented together to remove a glass air transition. The cement had to work under the extreme temperatures and the vacuum, without evaporating. The possible consequences were the lens would fall apart or the cement could end up con the face of the lens elements clouding the view.

Lubrication

Even though the Carl Zeiss lenses were prime lenses they still have vital moving parts that need to operate smoothly. The aperture blades must open and close to vary to exposure and part of the lens must rotate to vary the focus. These areas are normally lubricated for operation in Earth’s mild atmosphere.

Therefore the common lubricants used for the mechanical components of the aperture and shutter were unsuitable, as these result in condensation which could then gather on the glass surfaces.

Christian Ludwig, head of the optical design department for camera lenses at that time, remembers: “We tested the functionality of the system under the most extreme conditions that we could simulate. It turned out that the technology of the lenses used, including the Planar 2,8/80 mm and Tessar 5,6/250 mm, was suitable without any need for mechanical modifications. However, the specially produced Biogon 5,6/60 mm posed a major challenge, particularly due to the tight time schedule involved.”

A Hasselblad 500EL model known as the “Data Camera” fitted with a Zeiss Biogon 5.6/60 mm was esspecially built for moon photography. It featured a Reseau plate through which measuring points positioned with extreme precision were exposed in the image and were subsequently used for the photogrammetric evaluation of the images.

The cameras and lenses were left on the by all the Apollo missions. The astronauts only brought home the detachable film backs.

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The copyright of the article Carl Zeiss Walking on the Moon With Armstrong in Photography is owned by Philip Northeast. Permission to republish Carl Zeiss Walking on the Moon With Armstrong in print or online must be granted by the author in writing.