No magazine in Britain has the resources to do the first, though some pretend to, and it's very unlikely anyone would publish the result if they did. A completely objective test would reveal that some equipment is actually better than others. This is a position which publishers and manufacturers find mutually uncomfortable.
So, if you're after a firm indication of whether the Contax AX benchmarks alongside a Nikon F4 or a Canon EOS-1n, forget it. What you get here is a vague idea of whether any autofocus SLR is actually worth bothering with, based on a few frames snapped under conditions so undemanding they hardly constitute a test.
The fact that my 'benchmark' camera - a Minolta Dynax 9xi - fared no better than the AX came a disappointment to me, as on the whole it has proved slightly above average. Here's the nature of this first trial, and from it I can only say that the Contax AX is probably as good an autofocus camera as any SLR made.
We took our dogs on to the beach, got them to lope around a bit and occasionally manage a straight-line run towards the camera. Shirley and Ailsa kept them moving and I shot a couple of rolls of Agfa's Optima 200 colour neg film, one in each camera. The Contax AX was fitted with a 180mm �2.8 Zeiss Sonnar telephoto, and the Minolta 9xi with an 80-200mm � 2.8 Apo Minolta set to around 180mm.
The first few shots on the AX were disastrous - I had set the camera's complicated and comprehensive controls so that it did not lock out unfocused exposures and fired at five frames a second. 'First pressure' on the shutter release secured three totally unsharp frames instead of a meter reading.
A few seconds later the Contax controls were safely set to S for single frame exposure, SAF for single-frame 'lock out' focus priority instead of CAF, and P for Program.
My first comment is that with a 180mm lens and randomly-moving subjects, repeated manual refocusing of the lens was necessary to allow the AF to work. It seemed capable of tackling shots from 'distant' to around ten feet before reaching the limit of its 10mm film plane focusing action; at this point, more than a mere twist of the lens was needed, as the 180mm Sonnar completes a 180� half-turn to go from infinity to 7 feet.
Moreover, any error - like focusing too close - locked the focus out once again. In practice, you could not reasonably expect to switch from distant to close subjects or track random movements in the middle distance without considerable experience.
When shooting, I was convinced that the Contax AX was failing to focus correctly. The viewfinder image was almost always blurred when the shutter fired. I was surprised to find that the image on the film was not. Even with fast and unpredictable movements of a difficult subject - a white shaggy dog on sand - the Contax had focused pretty accurately, tending to fix the point just a fraction further away than the subject when it was approaching the camera.
The Dynax 9xi, in contrast, appeared to track the moving dogs perfectly, once its wide-zone focus has been turned off in favour of single-zone central spot focusing. The wide zone focusing is not ideal for a single subject kept in the centre of the frame!
In this case, I was certain that the Dynax pictures would all be sharp. Well, they weren't - like the AX, the camera consistently failed to ' predict' the final position of the subject perfectly. The program exposure also set a wider aperture and faster shutter speed, which in some ways produced a better result than the Contax, but a typical head-on action shot was focused on the dog's back with the face just slightly unsharp.
Close examination of both sets of negatives showed that neither camera achieved perfect focus on approaching subjects, though both did with across-frame or oblique movement. As that kind of movement presents not the slightest problem to manual focus users, any objective assessment would have to question the value of autofocus for action work.
The Contax AX, despite earlier doubts, proved just as capable of tracking action, catching suddenly framed images, and selecting the correct focus setting as the Dynax. However, whatever superiority Zeiss may claim for the 180mm �2.8 Sonnar and their other prime lenses, I found it impossible to tell between this lens and the Minolta Apo zoom. Confronted with a static subject, both cameras produced stunningly crisp images which looked better than the scene had appeared to the eye. Their AF on static targets was spot-on.
This is just a first test of the AX with one lens (we also have a 28mm here, and are awaiting various other optical bits to try with the camera). I have many other things to investigate about the AX and specific aspects of its use- we want to find out how well it autofocuses using secondary optical systems like microscopes, how it handles Hasselblad lenses via the adaptor made for them, and so on.
What is clear is that the AX, despite a degree of reticence on the part of Contax when high-speed sports or action subjects are suggested for a comparison test, will probably do far better than the prototypes led us to believe. The idea of a camera shunting the entire film, shutter, mirror and prism assembly back and forth to achieve autofocus with manual lenses lacks theoretical elegance, but the Kyocera ceramic engineering used to achieve it has proved successful and given the mechanism a speed to match ' driven' AF lens systems like the Dynax, if not Canon and Nikon's new technologies.
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