Nexus wet supplementary lens

by Mark Webster

Reproduced from in focus 68 (June 2002)

How often have you found yourself close to that perfect macro subject with your 105mm lens only to find that it is just too small to fill the frame? It is at times like these that you wish you had put on that +2 or +3 diopter which would give you that extra magnification. Fitting a diopter, extension ring or tele-converter can be very committing for a dive, unless you are certain that subject will be there - a better alternative would be a wet close up diopter rather like those available for the Nikonos/Sea & Sea camera systems. Well now that solution is available from the Japanese manufacturer Nexus and I have found it to be extremely usefuI in many situations.

Nexus wet supplementary lens

There are two versions of the wet lens available - firstly a single glass element lens mounted in aluminum with a flexible silicone skirt costing $61 plus $22.5 P&P and secondly a twin element sealed unit that is designed only to fit the Nexus 105mm port and costs $250. I had good reports of the single element lens from some American photographers and at the relative bargain price decided to give it a try.

The lenses are supplied in two sizes 90 and 100mm diameter, but they are both a little small to fit to a standard Subal port. However, I use 'third party,' small diameter, ports with my Subal housing so the lens I bought fits well as standard. It would not be too much of a challenge to make up a mounting ring to fit the front of the standard Subal port and the performance seems to be unaffected by the distance from the lens.

Nexus wet supplementary lens on Subal housing