Friday, January 26, 2007

Image Stabilizer Technology

It seems every decade something new and exciting happens in photo hardware. In the seventies we saw the arrival of accurate auto-exposure. This proved a great boon as we could stop having to constantly fiddle with light readings and camera settings and concentrate on the important aspects of picture taking. Viable auto-focus materialized in the late eighties and opened up a whole new range of possibilities in bird action photography. This decade has mostly seen refinements in earlier concepts and there is no doubt that, for example, both auto-exposure and auto-focus has greatly improved just lately.

However we had to wait until almost the end of the nineties for another really useful innovation. This time it crept in on the scene with rather less fanfare than usual, but there is no doubt in my mind image stabilizing technology is the great breakthrough of the decade. At last it is possible to produce sharp images without being encumbered with a heavy tripod. Image stabilizers have been around for a while in the home video recorder market, but have only recently has this technology become available to the stills photographer. As with a number of the previous breakthroughs this innovation was introduced by Canon.

I like to think I keep my equipment very current by buying all the latest stuff, but this time my wife Wendy jumped in ahead of me and placed an order for a Canon 300mm f4 Image Stabilizer lens. Since we always photograph together, we long ago gave up any attempt to share or pool our photo equipment. Almost every photo opportunity requires a specific lens and if there is only one of these among two photographers we found that whoever does not get to use the required piece of equipment will invariably dissolve into tantrums of grumpiness. We soon learnt that separate camera bags full of our own individual gear are essential. Any attempt at sharing simply introduced unnecessary turbulence into an otherwise fairly placid and stable marriage. When the Image Stabilizer arrived, Wendy jealously guarded the new piece of equipment, and it became clear that I would need a very good reason to try out the new lens for myself. It was only on the pretext that I simply had to review the Image Stabilizer for the benefit of Photography in Progress readers that I managed to lay my hands on the coveted piece of equipment.

Whenever I need to test new equipment or techniques I invariably head for my nearest Bird Park. Although zoo images seldom have the power of truly wild photography, the sheer number of opportunities make this an ideal testing ground. Firstly I was struck by the speed that I could frame and take pictures. Usually it requires several seconds to set up a tripod to the correct height and get the camera mounted on the quick release plate, frequently resulting in missed opportunities. With the Image Stabilizer lens I could get onto a subject in an instant. The stabilizing function is activated by pressing the shutter button half-way which also activates auto-focus at the same time. It takes a split second for the stabilizer to kick in after which the image almost appears to float in the viewfinder. The system detects the tiny movements resulting from hand holding the camera and continuously adjusts for these.

After shooting three or four rolls at the Bird Park I rushed off to the processing lab to get a quick review of the results. Generally when hand holding a lens it is necessary to use a shutter speed of the same value as the focal length. In other words a conventional 300mm lens will require a shutter speed of one three hundredth of a second or less to ensure most pictures are sharp. On my test rolls the images taken at one hundred and twenty fifth of a second with the 300mm Image Stabilizer were all sharp. This was indeed encouraging, but it was the test frames taken at a mere one thirtieth of a second that produced the most significant results with at least 70% pin sharp. Hand holding a conventional 300mm lens at such a slow speed would normally mean that you could consider yourself lucky to average even 10% sharp. At even lower speeds the success rate did drop off noticeably with one eighth of a second being the slowest speed that the system could cope with. I also tried shooting some frames with a 1.4 times converter added to the lens effectively making the 300mm f4 into a 420mm f5.6. This reduced the success rate marginally but the results were still vastly superior to that possible when hand holding a conventional outfit.

Although the percentage of sharp pictures when hand holding the Image Stabilizer at slow speeds will never be as high as when using a tripod and cable release, the sheer mobility and lightness of the system makes this a valuable tool in a number of situations. On a serious birding trip, where photography is of secondary importance, the ability to take sharp 'grab shot' pictures without having to lug a tripod around all day will be a wonderful advantage. Also at popular camp and picnic sites in our game reserves, the bird-life is often sufficiently habituated to allow for tight portraits with a 300mm lens. Here the ability to move quietly without a tripod, and frame subjects quickly will bring a wealth of photo opportunities. This winter I shall be working intensively in the Kruger National Park. As well as the ever present hornbills and glossy starlings, in the Kruger campsites, barbets and various woodpeckers are also very tame so I am hoping to get good pictures of these with the Image Stabilizer.

Of course this lens will have many advantages in the broader sphere of general wildlife photography. On walking trails it will be great for game photography. I recently tried using the Image Stabilizer from my vehicle with the engine still running – a situation that usually guarantees blurred pictures. The resulting shots of a cheetah were pin sharp even at one thirtieth of a second in very low light. I have also been photographing for a book on meerkats lately and once again the mobility of this outfit has been a huge advantage. Meerkats can move pretty quickly when foraging but with the Image Stabilizer I found I missed far less shots than in the past when I had been fumbling around with a tripod.

In fact the only bad thing about this lens is that at the moment we have only one, and Wendy and I are still fighting about who gets to use it. I must admit that I do sometimes forget that it is actually her lens and grab it without even asking, as a result that she now keeps her camera bag firmly zipped up and out of my reach! The only solution is going to be the purchase of a second 300mm Image Stabilizer to stop the squabbles in the Dennis family!

Getaway Guide to Wildlife Photography

Based on 20 years of travelling through southern Africa’s finest game reserves the author imparts much of his hard earned wisdom in a straightforward way that simplifies the technical complexities of wild life photography. With both digital and film media the art of making a picture come alive lies in its composition and lighting. Nigel shows the reader how to recognize ‘golden light’ as well as valuable advice on how to greatly improve the appearance of a photograph in other less than ideal lighting situations. Even the more complex aspects of photography such as selecting the appropriate aperture and shutter speed, making exposure compensations, and fill flash techniques are explained in clear simple terms. Apart from the invaluable photographic advice offered the author shares South Africa’s best-kept wildlife secrets: where to go to photograph wildlife, the best time of year to visit, and the game species you are most likely to find as subjects in each reserve. Reviews include '...the most useful book on wildlife photography I have ever read'.