Author: Andrew

An electrical engineer, amateur astronomer, and diver, living and working on the island of Hawaiʻi.

A New Family Member

Meet Electra, the newest addition to the Cooper household. Today we came back from the Kona Humane Society with a kitten. As per household tradition the name is that of a star, 17 Tauri, one of the brightest in the Pleiades star cluster.

Electra
A new kitten in the house, introducing Electra
You may notice the photo is slightly blurred, much like an electron this kitten never stops moving. Getting a decent photo is proving challenging. I am going to have to break out a faster camera than my little G11. Perhaps a DSLR in high speed burst mode can do the job, then again, maybe not.

It has been three months since we buried Adhara, three months with an empty, cat-less house. There has been something missing around this place. No fur-face looking to curl up with you when you get comfortable. No begging eyes at your feet when breaking up a roast chicken.

Meanwhile this little flash of fur has been streaking all over the house. Finding the interesting places. In and out and under everything. There are things we humans need to put away, out of little paws reach. There are other places where kittens should not go, a couple of those have been found already. But then, some things are learned only through impact.

High speed, wood floor, and screen door… Thud.

Yeah, saw that one coming.

Eventually she might slow down. Maybe? Perhaps? Before midnight?

After years of living with two elderly and mostly sedentary cats, a kitten is a real change. It will take time for us to come to know one another, eventually we will learn the routine. No regrets, I am truly looking forward to having a cat around again.

Did I say cat? Make that cats, there will be two. A second little fellow has been selected, but he is not yet ready to come home, a little surgery awaits before we can go collect him and complete the family. I will have to introduce him in a later post.

A Dummy Battery Adapter for the Canon 20Da

Another quick project to solve a little equipment issue. I realized I had a problem the morning before I was planning to spend a night shooting astrophotos up on the mountain. The batteries for my 20Da are old and do not hold a charge, no way I was going to be able to use the camera through the night.

The Regulator Installed
The regulator circuit installed inside the battery shell and connected to the existing contacts
The camera is an older model that remains quite valuable to me as it has been adapted to shoot astrophotos. The 20Da model differed from the standard 20D in having live focus and a re-tuned red cutoff filter that allows the glowing red of nebulae to reach the sensor. After seven years I still use the camera regularly.

I have the AC power supply for the 20Da, this is what I have been using for some time now. Shooting astrophotos in the driveway allows access to AC power. For field use this will not do, I need to operate fully from battery power. The camera batteries that I do have for the camera are now at least six years old, and do not hold enough charge to last.

Without AC power available I needed something that could plug into one of my 12V field battery packs. I really did not want to cut up the existing AC power supply to create a version to be used with an external battery. Plus, Canon used odd, proprietary connectors on the supply. (I really hate it when they do that!) I can not even use parts of the AC supply without modification.

With only a few hours available I came up with a plan. A little digging showed I had all of the needed components on-hand. Off to the work bench!

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The Moon, Mars, Saturn and Spica

A nice conjunction of a crescent Moon, Mars, Saturn and the bright star Spica will grace the evening sky tonight. All four will be within 12° of each other. The two planets and the star will all be about 1st magnitude, with the Moon showing about 37% illuminated.

The same quartet will get together again next month, for an even tighter grouping.

A Morning at Three Tables

With the south shores of Oahu denied us by rough conditions, we spent a day diving the north shore of the island. The specified rendezvous was a site known to local divers as Three Tables for a little shore diving. With an iPhone and Google Maps in hand, Deb and I drove across the island along unfamiliar roads to Oahu’s famous North Shore.

Three Tables
The beach at Three Tables, North Shore, Oahu as seen from the parking lot, photo by Deborah
What greeted us was a pleasant surprise. A small, sandy beach fronted a very interesting cove. Parking was just above the beach, we would not need to carry the gear very far at all. The “Three Tables” were an obvious set of flat rocks just out from the beach.

There were quite a few divers already present, including a class just getting their certification. Our group just added to the party. Charles and Jeannie, who had been with us on the previous day’s aborted dive at the YO-257. Another visitor from Texas, Ray, joined us for the dive.

Leading the dive would be Gabe Scotti, the owner of Kaimana Divers. Christine would be his backup. While Gabe led off, Christine would play the caboose, riding herd on the group. It was a nice day to be diving, we chatted while setting up the gear. It was a relaxed, Hawaiian style morning.

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