There is something so downright terrifying about an adult crocodile that the poorer the light, the greater the sense of horror and threat. It is the most primeval of all animals and the bigger it comes, the more it elicits a sense of dropping into a Spielberg movie.

This photograph of a four-meter-long male crocodile is elevated by the lighting conditions at dusk. Three hours before, it was all too bright and any photographs would be less dramatic. He is believed to be over 110 years old and weighs more than 750 kgs.

I am not good with crocs and I do tend to suffer from camera shake more than when filming any other animal. I have a steady hand, but not so much in encounters such as this. The other problem I have, is that when the camera is head on to a subject, there is always a decision to be taken as to whether to focus on the mouth or the eyes. It’s a dilemma for me because my default position is to have the eyes in focus and make sure that the nearest feature to the camera is not so out of the focal plane as to create a tension point. In most cases, however, that is not an issue and the face is all in focus.

But with an adult crocodile, the filmmaker must make a choice, as the distance from the nose and teeth to the eyes is material. I don’t think there is a choice; the focus should be on the nose and this photograph offers some big clues as to why.

I could not have taken this image 20 years ago. Cameras and lenses work so much better in low light than they used to and I was pushing my camera to the edge of its capability. I was also pushing myself to the edge of mine.