Saturday, 25 March 2017

Subtleties of light

As an astro-photographer, one is used to digging deep for the light needed for a good image of a very faint scene and working around the limits involved. Exposure time is limited by focal length to avoid "trailing" stars, we lose a couple of f-stops to avoid chroma effects (costing more light) and higher ISO means more noise. Still, it's not hard to get some nice results, as this image of the Milky Way and the shape the Australian Aborigines call The Emu, shows.
EOS 5D MKIV, 17-40mm lens at f/4, ISO 8000, 25 seconds
Sunrises here sometimes provide great subjects although it is hard to capture all the detail despite using HDR-type bracketed exposures. It doesn't help that the light show is often half over before you notice it and get shooting under time pressure.
Lake Glenmaggie dawn
A recent trip to Lakes Entrance had me up and about before dawn trying for the iconic shot. Alas, a big gap between expectations and result, although I was happy enough with the end result of this image of a local dredge. Took about 30 shots to get it as I wanted and, of course, the light is ever-changing at this time of day.
EOS60D, 16-300mm at 26mm, f/14, ISO 100, 1/50 sec
Trying to capture birds in dense bush also has its challenges, as these shots taken during a recent trip to the Tarra Bulga NP show. I usually shoot at 1/1000th second to counter any movement, a wide-open lens for shallow depth of field and auto ISO to get the needed light. However, the dense bush and tree ferns at Tarra Bulga reduce the available light so one has to experiment a bit and hope the birds stay around. Luckily, these two did but you can see the strain in the photos.
Olive Whistler (Pachycephala olivacea olivacea)
EOS 5D MKIV, 150-500mm at 500mm, f/6.3, ISO 500, 1/200th with +1.7Ev
Rufous Fantail (Rhipdura rufifrons rufifrons)
EOS 5D MKIV, 150-500mm at 500mm, f/6.3, ISO 500, 1/200th with +1.7Ev
Of course, every now and then, everything is right to get a shot like this (it helps that they be bribed with some seed):
Rainbow Lorikeet (Trichglossus moluccanus moluccanus)
EOS60D, 16-300mm at 300m, f/8,1/400th second, ISO 500

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