drsteve

the cage looks so small.......  

I prefer to think of it as "The sharks look so big....."

Your comment about the strobes is quite perceptive.  I actually had two strobe problems.  First was that my strobe controller was acting up.  I have been using the Heinrichs controller for several years and it has been very reliable, but on this trip it was acting weird.  I was getting complete strobe failures and some overly hot exposures.  It was heartbreaking to have one of these huge sea lions pose in front of my camera and then to have the strobe fail.  The other problem was the sea lions themselves.  On a number of occasions I would position a strobe and then one of these mischievous little devils would "reposition" it for me.  I eventually gave up on the strobes and shot natural light.  The first and third images had reasonable exposures, but the second image is natural.  The water was pretty dark because it was overcast and the water was pretty green.  The fourth image was shot by a friend.  It was pretty dark and I had to do some pretty serious dust removal to make it presentable.

I leave my rig assembled for each trip and break it down at the end for transport.  If you are boat diving everything stays pretty clean.  I will add one tip that I haven't heard from others.  After I rinse my housing in fresh water and dry the surface, I use a "rocket jet" air bulb to blow the water out of the control button holes.  I also go around the main o-ring to remove as much water as possible.  I do this every time before opening the housing.  Not only does this prevent stray droplets from getting inside when I am replacing the battery or flash card, it helps reduce the residual water that drys in the control stems, reducing salt buildup.  Despite the name, the rocket jet produces a very gentle puff of air which is completely safe.  It is intended for dusting off coated optics (which it also does well).

I will also add that if you are mechanically minded a complete overhaul of the housing is completely doable as a DIY repair.  It isn't rocket science.  Last year I bought the service kit for my Aquatica housing and replaced all of o-rings including the ones for knobs, buttons, levers, and display windows.  Warning: there are a LOT more o-rings than you realize; something like 40, although many of them such as around the windows, probably don't need to be replaced.  In fact I was pleasantly surprised at how clean everything was despite having dived it pretty heavily for over 4 years.  Very few of the o-rings showed any signs of wear and although there were signs of salt accumulation on the shafts, there was nothing excessive.  The only caveat is to make sure that you dive the housing empty to pressure test it before trusting it with the camera.

While rectilinear lenses are the best choice because they are the most versatile don't be afraid of fisheye lenses. They are useless unless you can get very close to your subject but they allow you to get very bright, high contrast images. Here is an example.


Manta Fisheye by - drsteve -, on Flickr

man, you lucky things being over there! Typical that there is a darn fishing hook in the mouth of the first shark! Isn't it meant to be a protected area over there?!

Yes, that is a rusty fish-hook in his mouth, and yes it is in a biosphere reserve where fishing is prohibited.  However, there is rampant poaching.  The dive boats are essentially the only eyes on the water and it is so far out that there is very little enforcement.  This particular Galapagos shark also had a scientific tag behind its dorsal fin which you can see on the second image.