After lots of struggling I’ve finally finished two DIY projects using fiber optic cables in underwater photography (last summer). It was an old idea mainly inspired by Joris van den Heuvel over at fuzzcraft.com but other inspirations also came from the wetpixel.com community (Alex Mustard’s home made ring flash and the fibresnoot by Phil). I don’t have two small strobes but one and I’ve found Alex’s solution a bit bulky, so I went on the fiber optic route.
My add on to the previous DIY project was that I had used the hook side of Velcro tape to space the fibers.
After putting some glue on it I’ve covered with the “loop” side and pressed overnight under heavy books. I’ve used heat shrink tubes to hold together the strands. These branches have been sewn at the Velcro part to an oblong rubber band providing a support for the whole set-up. (see picture below).
Next thing was to connect the fibers to the strobe. I’ve drilled wholes into a plastic piece (found in the kitchen but in the first version I used a Lego block) and pushed through the fiber bundles and glued them tight. Actually it was quite complicated because I haven’t left enough overhangs for the branches. When the glue has dried and hardened completely I cut and polished the fibers. The whole adapter was fixed on the port by Velcro (sewn on the rubber band) and by a buckle (good Velcro alone is probably fine).
See the “werkphotos” here:
I’ve tested recently the adapter in Croatia in the Adriatic sea. I had limited time and I did only 6 dives. The whole rig worked quite well with my sigma 50mm macro (see some pictures below):
More pictures you can see here:
I’ve also tested with a 100mm macro but due to the long port to subject distance, the strobe power was just not enough. At f11 and iso200 the pictures were only correctly exposed at the closest distance with bright subjects. In addition I haven’t seen much advantage over using a simple strobe placed above or right above the port. The big advantage of the adapter was that after realizing that the power through the fiber optics is not enough I just simply repositioned my strobe and used as a standard external strobe.