Issue 309: Behind the cover

The Hall of the Thirteen
in the Gouffre Berger, France

This image was taken in the Hall of the Thirteen, in the Gouffre Berger system, during the 70th anniversary of its discovery.

I was commissioned by Méandre Technologie to produce an image as part of a technical demonstration. The objective was to fully illuminate the chamber using more than 120,000 lumens, revealing the space in a way it had never been seen before, and allowing the many visitors present that day – during the Berger camp – to experience it under these conditions.

The main challenge was logistics. A significant amount of equipment had to be transported underground. A key part of the operation relied on Clément Sage, technical advisor for the French Cave Rescue, who carried a 25kg pack containing most of the lighting system.

The photograph was taken without any flash, using only continuous lighting. The final image therefore closely reflects what could actually be seen by the human eye at that moment.

Technically, the image is a composite of five horizontal frames, shot at 13mm on a Fujifilm X-H2S, to achieve an ultra-wide vertical field of view while maintaining a high level of detail.

Beyond the technical aspects, this image documents a specific moment: when one of the most iconic chambers in caving was, for the first time, fully revealed to the human eye.

Thibault Poinas