Let’s face it, it’s hard to obtain sufficient magnification to make pleasing images of wildlife with shorter telephoto lenses. It is possible to achieve good images without having extra long (super telephoto) lenses, but it’s much harder to get the magnification you want. Super telephotos make your shooting far more effective and enjoyable, yet even with them the focal lengths may not be enough at times. One way to overcome this shortness deficiency is to buy and use teleconverters, that are small lenses, which are designed to fit between your lens and camera.
The most common teleconverter sizes are:
– 1.4x – enlarges your lens’ focal length by 40%, so a 300mm lens becomes 300 x 1.4 = 420mm (loss of 1 stop of light)
– 2.0x – enlarges your lens’ focal length by 100%, so a 300mm lens becomes 300 x 2.0 = 600mm (loss of 2 stops of light)
The best thing is also that if you use a camera with a crop sensor, then the actual field of view will also change. It will be the total focal length of the lens multiplied by the crop factor. So if you use a 300mm f/2.8 lens coupled with a 2x teleconverter, you will have a 600mm f/5.6 lens (since adding the 2x teleconverter will equal the loss of two stops of light). On an APS-C sensor (1.6x crop factor) the lens will have a field of view equal to 600 x 1.6 = 960mm. However, you would need to consider your shutter speeds you choose to shoot at this apparent long focal length, because due to this crop factor of 1.6 the 1/FL rule of shutter speed selection will require you to use a shutter speed at least 1/960th of a second, with 1/1000th being the closest to this number.
I find it rather strange, and perhaps funny, that the number of people I hear complain about or dislike using a 2x converter is far more than those who advocate their use. Why would that be? I suspect there are a number of reasons, but one may be that they lack good quality equipment or they just don’t go out and shoot often enough to get used to the limitations within which they could get great results using these pieces of glass that increase the lens’ magnification. Or perhaps they don’t have good long lens shooting technique to achieve good results. Let me clear one thing up. Of course one will see some image degradation when slapping a 2x converter between a lens and a camera. This degradation will be even more when the lens, converter (or both) are of inferior quality. I mean, not your Canon L-grade converters; do note that Canon don’t make any converter other than the L-designated, luxury, models. I suspect that Nikon are in the same boat as well. My good friend Stephen Davey has bought the new Nikon 2.0x converter about a year ago and his test shots with it, using his D3 and 600mm f/4 lens were just mind-blowing. It all comes down to technique and lens to subject distance. You simply, cannot use stacked (or any) converters and shoot a subject from 100m or more away expecting world class results. However, if you get close, then even stacking your converters will yield exceptionally good quality images. Needless to say that you still need to have good long-lens technique and a little bit of luck. But both go hand-in-hand with photographing wildlife. You need to know what you are doing, how and know your subjects, know their behaviour and learn to read them like a book.
The below image here was made yesterday morning with a very cooperative bird in Castlereagh, who was only too busy advertising his territory. My mate from Brisbane, and I, were taking hundreds of photos of this same individual Golden-headed Cisticola a week ago. I knew where he would pop-up to call, so I just had to stand just within 5m of this branch and he would come. That he did many times over an hour. I was so excited to see this image on the computer. I love it when my plan gets executed just how I like it. Note, the light was quite bad this morning and I was using fill flash to brighten the bird against a stormy sky, yet it looks (to me at least) like natural light.
Whatever you do, wherever you are, don’t be afraid to shoot, experiment and learn. The more you shoot, the better your images become. I am eternally grateful to my wonderful wife and for the many subjects who (sometimes) cooperate with me. The best thing about getting this image (and the others before) that no call playback was used at all.
Stay safe and happy shooting.