MastCam

Some parts of the job are simply fun. Installing the various upgrades to the weather system has been just that. The latest piece of kit being more fun than usual.

Weather Mast
The Keck weather mast with a sonic anemometer at top, MastCam, and the housings for the temperature, humidity and barometric pressure sensors.
We are installing a number of new cameras throughout the facility. Replacing an ancient CCTV system that still uses composite video and black and white monitors. Yeah, that ancient. The system is quite useful, it allows visibility of the telescopes from the operator stations and the manual control panels when you are driving the telescope.

Even that is topped by the camera I installed this fall. The latest camera is a new pan-tilt-zoom camera attached to the weather mast.

The camera does have more prosaic reasons to justify the effort of installing it. With the camera the operators can observe the weather conditions around the telescope, observing supervisors can view the ice and snow on the domes from Waimea, the day crew can check the weather conditions before driving to the summit, and more. The camera does have enough sensitivity to see the brighter stars and the banks of fog that roll over the summit. In full dark and at full gain the image is noisy and faint, not all that great. Given just a little moonlight the performance is much better, allowing visibility of oncoming clouds.

MastCam Ice
Hanging ice blocks the view of MastCam after a severe winter storm on January 4th, 2015
Weather conditions can be extreme on the summit. Last week’s storm being a good example… 100mph sustained winds, 135mph gusts, more than a foot of ice coating any vertical surface and several inches on the ground. The camera is rated to survive such conditions, and has now survived its first major winter storm. Electronic operation is guaranteed by the manufacturer for -40°C, and there is a heater and blower inside the camera dome to remove ice. It was able to melt its way clear, at least partially on the first day, while it took a week to clear the domes for operation.

Even more fun! On Christmas Eve I was contacted by Hawaii News Now for photos of the storm, they were eager to do something about a white Christmas for the evening news. As I had not been to the summit and no one on our crew was up, I simply grabbed some MastCam images and forwarded them. The images were aired in the first couple minutes of the Honolulu evening news!

The camera is not available to the public, it would be too much wear and tear to the pan-tilt mechanism and a huge hog of bandwidth. You have to be inside the Keck network to use, from there it is available to anyone on staff. It has proven quite popular, with many folks using the imagery to check on mountain conditions in the latest bad weather.

Next up, yet more cameras in the dome and even a couple on top of the domes. there is also a precipitation sensor and more in the works for the weather station.

OK, enough fun, back to revising the Keck 2 dome schematics.

Snow on Mauna Kea

Not a great deal of snow, maybe an inch or two rearranged by the winds. More snow is expected over the coming few days before this storm is over. Where to find the heaviest snow on the mountain? Puʻu Poliʻahu of course, just look at the images below.

This is the first winter storm that our new weather mast camera is operating, since I bolted it in place a couple months ago. It is great fun to have a full pan-tilt-zoom camera available during weather events like this.

Summit Ridge Snow
The summit ridge with an inch of fresh snow
Subaru in the Snow
Snow around the Subaru telescope

Capturing the Mountian Shadow

A high quality pan-tilt-zoom camera on the roof of the observatory at an altitude of 13,630ft? Just too much fun. I have found myself logging into the camera at sunset to enjoy the view, or keeping the video in the corner of my screen through a Hawaiian blizzard. I have even forwarded images to a local television station when they requested views of a white Christmas in Hawaiʻi. Yes, they used them for the evening news!

Weather Mast
The Keck weather mast with a sonic anemometer at top, MastCam, and the housings for the temperature, humidity and barometric pressure sensors.
This camera can do more… The camera is an Axis Q6044-E dome style security camera. The camera contains a small Linux computer with a huge array of scripting and control options. Combined with a 720p HD camera, reasonably decent optics, and an accurate PTZ mechanism the camera is quite capable.

To make the best of this wonderful toy I need some tools. To that end several Python programs have been written, including a camera scheduler. This program takes a text file with a schedule and captures images at the programmed time and date. All of this was easy to implement in Python, all of the necessary ‘net protocol support is available in the libraries.

The schedule file can contain any number of separate schedules for multiple sequences. At the specified time the program insures the camera is set properly, moves the camera to the correct position and captures the image. Each sequence is saved to a unique directory and given a sequential name suitable for compiling time lapse video. Add a simple GUI to allow images and status to be monitored and the program becomes a very useful tool.

There are now multiple sequences running… Photos of the summit ridge at each sunset, the shadow of the GPS antenna every day at noon, the Kohala mountain every day mid-morning, the TMT construction site several times a day, and more.

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