Louis Vella, of Ely in Cambridgeshire, has taken a giant step in his photography: after extensive photo-taking during dive holidays in the Bahamas, the Maldives and Hurghada he has decided to upgrade from a MotorMarine II to a housed camera because he considers his Sea & Sea set-up has limitations.

Mind you, when you look at his pictures, many photographers would be more than pleased with his slides and prints because the MotorMarine and its accessories represent good value for money, are easy to use and can produce good results.

Just look at his shot of a bull shark taken at 28m in the Bahamas Shark Alley, using the MotorMarine's standard lens and popular YS50 strobe.

It is eye-catching, with the shark making a dramatic diagonal.

 

I also liked his close-up of the two clownfish in front of an anemone at The Temple, near Sharm El Sheikh, in the northern Red Sea. This makes a change from the traditional picture of clownfish nestling in the anemone's tentacles. Interestingly enough, although I can understand Louis' decision to move on to a housed camera, these are both the types of action shots which are easier to take with a viewfinder camera, such as Sea & Sea's MX10 and MotorMarine, or the Nikonos range.

This is because you must pre-set the distance on which the lens is focused and, therefore, only have to concentrate on the picture as you see it in the viewfinder or watch it develop between the framers of a close-up lens. A housed camera will produce an even better result because of the greater quality of the lenses available, and the superior way in which the camera's electronics will calculate the exposure in both natural light and with flash ... but you have to work for that improvement.

By contrast, Louis will find it easier to improve on his slide of his dive buddy swimming through glassfish at 15m on Gordon Reef, also in the northern Red Sea. This is because when he looks through the viewfinder of his Nikon F90X he will see virtually the picture which the camera will take - the viewfinder shows only 92 per cent of the shot, a factor which is not usually important.

If he was able to frame the photograph more tightly I think Louis would have tried to cut out some of the foreground which would increase the impact. This is also the type of shot which would be further improved if the diver was pointing a torch at the fish (but you need the intense beam of a video light for it to register on most slide films).

Sensibly, he has already bought his F90X and a 24-70mm zoom lens. This will give him time to get his head round the complications of such a sophisticated camera, which can be mind-boggling.

Louis is planning to buy a Subal housing and is pondering what additional lenses he will need. He is thinking of a 60mm macro lens and an 18mm wide-angle optic.

The Nikon 60mm macro lens is the great workhorse lens of underwater photography and will be a worthwhile investment. Opinions are divided on the 18mm lens: it produces excellent results but is considerably more expensive than its 20mm stablemate, which is almost as wide and also performs well. Personally, I would go for the 18mm lens if my budget allowed, because fewer photographers are using one so the results will be different. Otherwise, I would choose the 20mm lens and put the balance towards a 16mm full-frame fish-eye lens, which is much in vogue for wreck shots and close-focus, wide-angle work.

Finally, Louis asks whether it is correct that the maximum size of prints that can be obtained from 35mm slides is 7in x 5in. Any professional colour laboratory will produce larger prints. Good-quality slides will enlarge to 10in x 8in, but they have to be extremely good to go to 16in x 12in or even bigger.

Colour laboratories are listed in the Yellow Pages and especially in magazines for professional photographers. They are more expensive than the local chemist or mail-order firm, but usually more reliable and produce 'cleaner' results.