So why do I use big glass for wildlife photography? In some sense it goes against the old adage, ‘move, don’t zoom’. Often I see images of wildlife that have been taken with long focal length lenses, say 300mm plus, and the shooter then complaining about lack of clarity/sharpness in the image. I generally advise people that there are so many variables that can affect the clarity/sharpness of an image beyond just the stability of the camera and lens and good technique. The most common reason for this lack of clarity/sharpness is that shooting over long distances can sometimes be like shooting through a shower curtain: the atmosphere is rarely crystal clear except maybe after a storm or on one of those crisp winter days. Atmospheric ‘interference’ will adversely affect images taken at distance: heat shimmer, invisible dust in the air, ice crystals etc. If we want to create an image in these conditions then it makes sense to get closer to the subject. Big glass with long focal lengths just wont cut it. Hence, ‘move, don’t zoom’. And quite honestly, if you can’t get close enough for the shot without atmospherics badly affecting the outcome, then don’t take the shot. If you’re taking a shot with 500mm plus over say 100 meters in poor conditions like I’ve described then I guarantee the image will be soft, lack clarity and detail.
All that said, why do I use big glass? (I rarely shoot less that 400mm, usually 500mm and often with extenders. Unless I’m doing macro work).
I’m a wildlife photographer, not a photographer of wildlife. There’s a world of difference between the two. A wildlife photographer puts the animal first, has at least some understanding of its behaviour and knows that some human behaviours can negatively impact on the welfare of the creature. Wildlife photographers don’t take the shot if, as a result, the animal will be ‘disturbed’. So that’s my reason for using big glass with long focal lengths: I don’t want to intrude into the animal’s world and I want to keep any disturbance to an absolute minimum. I want to create images of animals as they go about their business without them being aware of me. I’m always after capturing that fleeting moment, that glimpse into an animal’s behaviour few people ever see. And if atmospherics get in the way then I don’t take the shot.