Yep.. the UCL 165 has a thread on the inner edge of the external ring to allow for stacking. The camera end of the lens can fit into either an adapter or the housing.
So far, I realise (like SSRA) that focusing at 105mm zoom in macro mode is tough. Hopefully by stacking 2 UCL165s together, I would be able to get better magnification at a lower zoom level, making it easier (the camera can be a little further away and focussing can be easier) to get some shots off for the tiny creatures (eg pygmy seahorses and that tiny squid in my gallery).
So far, I realise (like SSRA) that focusing at 105mm zoom in macro mode is tough. Hopefully by stacking 2 UCL165s together, I would be able to get better magnification at a lower zoom level, making it easier (the camera can be a little further away and focussing can be easier) to get some shots off for the tiny creatures (eg pygmy seahorses and that tiny squid in my gallery).
