There are people who love it, and people who hate it. But everyone still has to agree that the quality of the pictures taken with this camera are hard to beat. The image is always very sharp and it enables to take the best possible pictures, under the conditions available.
The main complaint one could have towards this camera is definitely the fact that it is not very user friendly. In terms of features and ease of use, the Nikonos doesn't seem to have evolved at all throughout the decades. Manual focus is extremely hard to set unless you're quite experienced, which results in many pictures being out of focus. It is really inaccurate trying to determine the distance from the subject underwater, especially because you'll usually be working with wide angle lenses, thus extremely close to your subject where a discrepancy of as little as 40 cm from what you've set may already mean you'll be out of focus. This also demands that the strobe be properly set to the distance you've determined, to avoid over or under exposure. This will make it all the more difficult to set when you're taking pictures with slide films, which allow much less margin for error in exposure than print film. Another problem is composing your picture. It is very hard to look through the viewfinder with your mask on, but this problem can be quite easily solved by adding on an extra enlarged viewfinder on top of the camera body. Even though the edges of the image on the viewfinder are quite distorted, it still makes it much easier to aim at your subjects by holding your hands forward, closer to the subject.
But once you finally got used to setting all the parameters properly, you will be rewarded with awesome results. The trick is to get past that threshold where more than half of your shots are useless. It's the same thing with land photography, and unless you persist, you won't get past shooting your third roll of film or so. Past this, the user will grow to appreciate this camera's robust built, and near zero probability of failure once you're underwater (as opposed to a Sea & Sea I've used once which once underwater simply wouldn't synchronize with the strobe!).
Land cameras inside a fiber glass box may be a good alternative, since you're able to get familiar with them outside of the water, and only then try it out in the sea. However, I've never had the pleasure (nor could I afford it, for that matter) of shooting with a camera inside a glass box. The main advantage would certainly be the ability to auto focus, and aiming through the enlarged viewfinder enclosed. You would be thus able to accurately set the strobe to the focused subject. I can't comment on the disavantages of this alternative system (e.g., loss in quality?) since as I've told, I haven't had the chance to use one so far.
Therefore, this camera is recommendable because it is fairly easy to find and rent from many dive shops, as opposed to fiber-glass boxes, which have to be made specifically to fit your camera, and this costs lots of $$$ (around 800 - 900 U$ depending on the model, from Ikelite). So the bottom line is; if you can afford it, go for the fibre-glass for the ease of use. If not, just keep trying on the Nikonos and you'll end up getting great results.
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