Mount Greenoch Lunar Eclipse


Mount Greenoch Lunar Eclipse

The tonne of astrophotography equipment that I hauled to Idaho and back for the total solar eclipse in August had remained in the shed until the week before this lunar eclipse, and most of it till eclipse day itself. With summer at Camp Cooinda and a job that doesn't shut down over the holiday period either it was time to dust things off, put them back together and hastily remember how to use them. A sensible approach would be to focus on just one or two cameras, but as usual I couldn't resist putting all my cameras into service and aiming for one of everything.. widefield, timelapse, composite, tele-photo and telescopic images of the eclipse.

Composite image of Lunar Eclipse
Canon 6D ISO200, Samyang 35mm lens f5.6
Exposures of 1/30 (partial phases) and 2 secs (totality) plus foreground twilight 

In advance I had booked two days of leave ready to travel a whole day in any direction if that's what it took, but the forecast didn't look good at all in either South Australia or NSW so heading north or west wasn't going to be any help to me on this occasion. Since I wasn't well prepared I chose to stay at home rather than the extensive effort required for only slightly better odds in north-east Victoria (Mt Buffalo again did cross my mind). Being at home offered many comforts; all the tools I might otherwise forget as well a dome to shield the scope from the wind and another solid pier with 240v power. In the end switching over scopes in the dome and trying to set that up proved more complex than I expected and was hardly worth the trouble.

After speaking to some local landowners, after dinner with Kaz I headed out along Mount Greenoch Rd towards Talbot to an area with a good view and some nice rustic ruins. The high cloud that was concerning in the forecast proved photogenic around sunset and I gave Fred Venderhaven's steam-punk bulb-ramping timelapse gear a good run in a strong and wintry-cold wind. As is often the case, moonrise on eclipse night almost steals the show and I ended up playing in the twilight so long that I had little time left at home to get the other gear running before the eclipse started.

Partial Phase soon after Totality, 0.5 sec, f13, ISO400
Canon 5D Mark IV, Takahashi FS102 with 1.6x extender

Polar alignment of my second mount proved very difficult with cloud and bright moonlight (who ever polar aligns under full moonlight?) - another area where a little preparation on night's before the eclipse would have paid dividends. But the high cloud was set in pretty solid around the Moon at this point so many of my imaging goals for the eclipse were already shot anyway, particularly an animated high-res view.

Prior to the solar eclipse in the States I'd done extensive work measuring focus at different temperatures to provide a manual form of temperature calibrated focus with my Takahashi FS-102 telescope. Over the next few hours on this Wednesday night as the temperature cooled down (only slightly), I proceeded to very carefully adjust focus on the scope in the wrong direction (without having to interrupt the rapid and automated sequence from Eclipse Maestro running on the little MacBook in the dome). So any remaining shots that weren't already compromised by high cloud were now rendered significantly less sharp than they should be due to carefully implemented poor focus. Add that to the list of frustrating astrophotography mistaked I've made - if only I'd had time and energy to practise for just an hour or two on a previous night :-(.

Partial Phases, 1/125, f13, ISO400
Canon 5D Mark IV, Takahashi FS102 with 1.6x extender

Totality, 8 secs, f13, ISO400
Canon 5D Mark IV, Takahashi FS102 with 1.6x extender
Note difference in exposure between sunlit and eclipsed Moon - 1/125 vs 8 seconds!

Visually the eclipse was enjoyable to follow between the cloud patches and it looked even better in 10x binoculars - highly recommended for eclipse viewing! Living at a dark site allowed full appreciation of the dramatic change in brightness from Full Moon to the dark of no moon. It's quite a strange feeling having the light on the landscape come back at the end of the eclipse and even reminsicent of the experience of a solar eclipse. The magpies thought so too as they started chortling at 2am in the morning, confused enough to think that daybreak was starting.

The cloud forecasts from the weather models were remarkable really - and Cloud Free Night is the only place where you can get the best short-term forecasts from BoM ACCESS models - if you're not using it you're not using the best information. In the image below, high-resolution ACCESS (City Scale) forecast is at the top, with actual conditions at eclipse time below. Unfortunately the high cloud extended just a few kms too far south.

ACCESS model cloud forecast from Cloud Free Night (top)
Satellite image of conditions at eclipse time (high cloud to north, low cloud south)

So a bit hit and miss from a photographic point of view, but enjoyable to watch regardless. Lucky we don't have to wait long for the next one - a winter eclipse in the wee morning hours of Saturday 28th July.