OASI: New Zealand skies

After some 40 years in the aerospace industry, I retired in autumn 2017. One of my first actions post-retirement, following a lifetime of anticipation, was to book a holiday to New Zealand. I must confess that my primary interest lay in the landscape and wildlife of the country and thoughts of astro-photography developed no further than aspiring to perhaps a shot of the night sky as a memory of my visit. So I packed no serious astro-photography assets in my travel bag.

I made the trip to New Zealand in April 2018, autumn in the southern hemisphere and, particularly in the west of South Island, dry, clear skies were rare. Indeed, as exemplified by my day on Milford Sound, cloud was the norm! (See picture below.) On a visit to Lake Tekapo, I had hoped to visit the University of Canterbury's Mt John Observatory above the town. However, gale force winds prevented any possibility of ascending the mountain. At Te Anau, the closest town to Milford Sound, skies were partly cloudy and there were many bright lights around the hotel. I could have driven out of town to darker skies - if only the beer were not so good!

I arrived at Wanaka and enjoyed the first really clear night. I set my Canon 100D with attached Tamron 18-200 mm lens to ISO 6400 and waited for night to fall. My technique was simple: find a flat surface, find something to prop up the camera pointing vertically then open the shutter for a few seconds. The night provided my first view of the Magellanic Clouds. I used an 8 s exposure for my first photograph of the nebulae (see below) as I struggled to hold the camera steady for longer. I also struggled to achieve accurate focus (due to the absence of a suitable distant focussing target) so defaulted to infinity focus.

I was happy with my photos from Wanaka and thought little more of the night sky as I moved to New Zealand’s North Island. I made a brief visit to the Carter Observatory above Wellington before moving on to Taupo. Unfortunately, although the sky was clear, an orange skyglow caused by light pollution prevented further astro-photography. Finally, I arrived on the coast at Tairua on the Coromandel Peninsula for my last couple of nights in New Zealand. At last, there was a (very) dark sky and, to the south, a clear view of the Milky Way. Using the technique described above but with greater concentration and practice I was able to take 30 s exposures. After taking several views across the sky, including the upside-down Orion constellation, I took a final shot with the lens "zoomed" to what I later found to be 135 mm. I had no specific view in mind: it was a "point and click". On examining the image later I found that I had benefitted from beginner's luck and had captured an almost perfectly framed picture of the Carina Nebula (NGC 3372) and the nearby sparse open cluster (NGC 3114)!

On returning home, with the assistance of my friend Peter Marriott, I used Photoshop to enhance the photographs, producing the images below. Camera settings were:

Milford Sound, 05 Apr 2018.

Large and Small Magellanic Clouds, 07 Apr 2018. (8 s exposure.)

Region around the Coalsack and Large Magellanic Cloud, 22 Apr 2018.

West of the Coalsack, through Carina to Canis Major, 22 Apr 2018.

Orion and Canis Major, 22 Apr 2018.

NGC 3372 (left) and NGC 3114 (right), 22 Apr 2018.