It’s important to remember that it’s a combination of light, composition and focus that make a photograph technically good, but expression and behaviour that make a wildlife photograph truly memorable.
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D300 + 300mm VR @ 1/100s f/3.2
Also, as far as Zoos go, it doesn’t get much better than Zurich. If you must shoot at a zoo, this is the place to go. Open spaces with animals flying and doing their thing around you are the best places to do immersive practice.
More on that in future!