New DECam Prime Focus Cage and Optics Installed

The DECam installation team meets to discuss the procedure prior to installing the new prime focus cage on the Blanco 4-m telescope

As part of the process of installing the new Dark Energy Camera on the CTIO Blanco 4-m telescope, the team meet to discuss the details of each major step before it takes place. This makes sure everyone understands what has to be done and maximizes the safety, both of personnel and equipment.

Victor Pictor works on the Blanco Telescope Cass cage

The Cass cage of the Blanco 4-m telescope must be reinforced to carry additional weight to balance the new Dark Energy Camera. Here master welder Victor Robledo is preparing surfaces for welding.

The DECam prime focus cage under the Blanco 4-m telescope before installation

The new prime focus cage, a major component of the new Dark Energy Camera, lies on its side under the Blanco 4-m telescope before it is installed. Steve Chappa of Fermilab inspects the optical alignment target which can be seen just in front of the front element - a very large, fused-silica lens.

The DECam prime focus cage under the Blanco 4-m telescope before installation

The new prime focus cage, a major component of the new Dark Energy Camera, lies on its side under the Blanco 4-m telescope before it is installed. The optical alignment target can be seen just in front of the front element - a very large, fused-silica lens.

The DECam prime focus cage stands under the Blanc 4-m telescope awaiting instalation

Some last-minute tests are carried out on the new DECam prime focus cage as it stands under the disassembled Blanco 4-m telescope the night before it is installed.

This is a tone-mapped, high-dynamic range image constructed of several photographs combined.

The DECam prime focus cage stands under the Blanc 4-m telescope awaiting instalation

The new DECam prime focus cage stands under the disassembled Blanco 4-m telescope the night before it is installed. The view is looking up alongside the cage through the barrel of the disassembled telescope (red) supported by the blue “horseshoe”. The square arrangement in the center are custom work platforms used by the crew when they attach the cage to the telescope. Two of six hexapod legs can be seen on the side of the cage.

This is a tone-mapped, high-dynamic range image constructed of several photographs combined.

The DECam prime focus cage is raised into position

With the Blanco 4-m telescope locked in a vertical position and the old prime focus cage removed, the new DECam prime focus cage is winched up to the top end to be installed. The new cage is braced by the yellow “strongbacks” and in the picture can be seen passing the center section approaching the work platforms.

The DECam prime focus cage is raised into position in the top ring

With the Blanco 4-m telescope locked in a vertical position and the old prime focus cage removed, the new DECam prime focus cage is winched up to the top end to be installed. The new cage is braced by the yellow “strongbacks” and in the picture can be seen nearly in position and surrounded by the installation team standing on custom work platforms.

The DECam prime focus cage is mounted in the top ring of the Blanco 4-m telescope

With the Blanco 4-m telescope locked in a vertical position and the old prime focus cage removed, the new DECam prime focus cage is bolted in place at the top of the telescope. The new cage is braced by the yellow “strongbacks” and in the picture can be seen being fixed in place using the “spider” legs (two can be identified by the orange and white stripes), and surrounded by the installation team standing on custom work platforms. The installed cage contains some of the largest lenses in the world.