March 20 2015 Total solar eclipse success
In Dubai & on my way home.
Despite the generally cloudy weather expected at this time of year, we saw an incredible solar eclipse under perfectly clear skies on Adventdalen glacier about 10km east of Longyearbyen on Spitzbergen Is, Svalbard. The temperature was a balmy -16 C as the eclipse started. As the sun disappeared, temps dropped to perhaps -23C. Different thermometers were reading between -20C and -30C. My freezer suit and NEOS overboots worked a treat. While some people were jumping around trying to keep warm, I had to unzip numerous times to release heat and prevent sweating. At other times on the trip, eg watching aurora at around -10C, I was far too hot and sweating. During the eclipse, my fingers got very mild frostbite from occasional battery changes or other actions where I had to remove my gloves. No marks on the skin, just a mild stinging sensation the next day.
I heard many tales of woe, of batteries that stopped working, LCD displays that froze, cameras that inexplicably stopped working. Many plastics became very brittle, and if you touched any metal with bare skin, you might get stuck to it.
I had put a bit of work into preparing for low temperatures with special lithium iron sulphide batteries similar to "Energizer lithium ultimate" powering the telescope drive and other items and normal Lithium ion batteries running the camera with a back up set of lithium iron sulphide AA batteries in the battery grip. lithium iron sulphide batteries have no liquid electrolytes and keep working to -40C. I also had chemical heater packs ready to use but didn't need them.
In the end, the only problem I had was that I initially left my cheap ebay rechareable lithium batteries in the camera and they stopped working after 2 exposures at 1st contact. When I changed over to the OEM batteries backed up with ultra low temp lithium, problem solved. Even though I had a note attached to the telescope reminding me to change to the good batteries, I managed to forget to do it for a short time.
My camera LCD display didn't freeze but it did slow down and give a few false displays of shutter speeds as the temperature dropped. But this didn't affect me as I don't look at the display during an eclipse and mostly all went without a hitch. My camera focusing in the cold left a little to be desired.
Congratulations to those who were successful and commiserations to those who were clouded out.
Having big problems with my IIS login, the image browser/attachment page thinks I'm logged out while the post page has me logged in?? Will add images when I'm back in Australia.
regards
Joe Cali
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