Marelux has just developed a new gadget for fellow macro underwater photographers, SOFT-Smart Optical Flash Tube.
This device can be used on various popular strobes, with an aiming light automatically switching off when strobe flashes. Light shape can be adjusted by a build-in aperture, which is controlled by an extenal dial. Focus point is 170mm from the end of the tube and the diameter is 2mm to 60mm.