dives

It must be spring

Spring has sprung – despite distinctly murky conditions on the James Eagan Lane this weekend, there were Oaten Pipe Hydroids (Tubularia indivisa) aplenty to see. The numbers of these marvellous creatures explode in early spring, that is until the nudibranch eggs hatch and they all get munched!ERB_0443

Nikon D500, Nikon AF-S 60mm with +5 diopter

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dives

Looking for skeletons

One of the pleasures of underwater photography is learning about sea life which many divers don’t even know exist. The Skeleton Shrimp (Caprella linearis) is one such species. They are not exactly tiny (up to 2cm long) and are actually really quite common. It’s just that they are very difficult to see. They spend their lives clinging to other sea life, grabbing food particles from the water. They are usually seen on hydroids, because they are easy to spot there, though they inhabit many other hosts which get them into the current, such as Dead Men’s Fingers, but are much harder to spot on those.

So it was, I spent a very enjoyable dive in Loch Creran recently hunting for these critters. They have often been photographed before and I wanted to make a different kind of image to what I had seen previously. By using a high-power diopter, I concentrated on just the head of the creature, shooting across the hydroid fronds. Shooting an abundant species allowed me to hunt down a suitable rock with a conveniently placed hydroid, so I could shoot without disturbing the fine silt ubiquitous at this site. I like this shot because it shows the shrimp through the fronds of the hydroid, like an elusive jungle animal seen through the undergrowth. The shallow depth of field of the diopter ensures subject separation by throwing the hydroid out of focus.

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On the other hand, this second capture unintentionally caught the shrimp with its claw arms wide. It made me smile because whereas the first image seemed to say “you can’t see me”, the second seemed to say “Ta-da! Here I am!!”

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Nikon D500 + micro Nikkor 105mm + Nauticam SMC.

equipment

Reassuring light

The worst nightmare for any underwater photographer is a flood. You know what they say: there are two types of underwater photographer- those that have flooded a housing, and those who haven’t…yet. Every time I get in the water with my camera, I always wonder if water will get into the housing. I think most underwater shooters have a ritual to follow when setting up the camera to avoid a leak, and I for one never used to deviate from mine. After all, some of the steps in my setting up process might be unnecessary, but my fear of a flood prevents me from changing the ritual.

Well, for a year now I have been using a leak detector, which lets me pressure test my housing before every dive, and it has made a massive difference to my confidence in how I have set up the housing (as well as allowing me to streamline my setting up ritual).

DSC_7365I use a device called Leak Sentinel, purchased from the very helpful Miso Milivojevic, who designed and manufactures them in Slovenia under the company name of Vivid Housings. The device fits into a spare strobe port on my housing; some of the air is evacuated from the housing with a small pump. If this under-pressure remains stable, then the housing has no leak and is safe to dive. The leak sentinel indicates this with a reassuring green flashing light.

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I have just upgraded mine with a new circuit board which adds some new features. The Leak Sentinel can now compensate for temperature changes (which are likely to affect the pressure and potentially cause a false positive); it now allows me to test the housing a day or so before the trip, and also warns me when the leak sensor battery is getting low.The device has already paid for itself because it detected a leak in the system, which I spotted and corrected, rather than finding out when I got in the water….