Seawater Blog

18. June 2011: Sunrise in the deep.

Eager to explore the potential in positioning the flashes far away, I decided to try to back light some sea fans. I went to a location 30 minutes from home, where the sea fans can be found at 25 metres. Usually, you have to go deeper to encounter corals in Nordic waters. The location is not far from an estuary. Unfortunately, the river brings a lot of mud and you have to take care, not to stir up the sediments. The visibility was 6-8 metres as soon as I got under the layer of freshwater. I found a nice fresh coral, not yet suffocated from the muddy river "Gaula", and decided to take some shots. I left the flash 40 cm behind the fan. I was able to position the sensor far enough to one side, so it came within reach of the camera flash. I really need a longer cord to the sensor.

I started 5 metres downstream the fan. It is important to keep downstream of the subject, to avoid too much dust in front of the camera. Equipped with a full frame camera and a 14 mm lens, I was able to get less than a meter from the coral and still capture the entire fan. It is important to get close under such conditions. After the first approach I had to wait for 5 minutes for the dust to drift away.

I made a new approach from a slightly different angle, this time with a second flash behind me. The frontal attach brought more light to my side of the fan, but I lost the contrast I had achieved in the first image series. It was no success, really.

I think the effect of the light positioned behind the motive is interesting, but very unnatural. It is probably better suited for wreck images where you want some dramatic effects to underline important wreck features. I will try this later and post the results here.

17. June 2011: Light is everything!

Anyone who has tried underwater photography in Nordic waters has experienced challenging conditions with little light and poor visibility. The answer is of course to bring your own light, preferably flashes. The problem is that dust and particles in the water tend to reflect the light. The images become foggy with little contrast. The answer to this problem is to position the flashes far away from the camera. But how do you make sure the flashes stay in the position where you left them? You estimate angles and distances with care, and the flashes really have to keep in position, despite any current or wave movements. The solution to this problem appeared after inviting my friend, Øyvind Hegle, a mechanical wizard, to hold my flashes during a dive at a local airplane wreck. A few days later he presented a solution. He made two handles from a piece of plastic and attached them to two clamps I bought. It looked like something directly out of Ikelite's catalogue.

The clamps were strong enough to hold the flash in an upright position. With a longer cord sensor, I can hide the flash well below the sight of the camera, and thereby create a pleasant background light. At this first dive there was not time to experiment as much as I wanted. I hope lack of experience and poor visibility are the main reasons for not producing any great shots this time.

I managed, however to prove the ability to create an evenly exposed image with no backscatter in poor visibility. I achieved this by positioning a flash on each side of me, 3-4 metres behind. The flash on the camera was directed backwards to trigger the main flashes. The result can be seen below. The visibility was approximately 6 metres. If the flashes had been positioned on the camera, the image would have been all fog, without enough contrast.

The next experiment will be a back lighted sea fan.

19. March 2011: Your dive is just half-done when you step out of the water...

.. my wife tells me. She is right, as always. Looking through the images the following day, I remembered a tiny creature I saw under a rock, towards the end of the dive. It looked like a juvenile crab, the carapace was less than 10 mm wide. Luckily, I took some shots. It turned out to be a long-clawed porcelain crab, the first porcelain crab and species no. 350 to enter seawater.no!

18. March 2011: You never know what you'll find...

It was windy, 0°C and dense snow showers. I love this time of year, because the period from January to April is the top nudibranch season. A large number of different species turn up on diveable depths. I really don't know where they come from, but they are back every year. So, this was a perfect day to visit my best nudibranch location. Steep, rocky formations are covered by hydroids, the favorite food of many nudibranchs.

Following my standard swimming path, at 32 metres I saw a sea star I had never encountered before. I cannot claim it was beautiful. It actually looked severely hit by some skin disease. I later learned that the bumpy skin is a characteristic feature of the Pterasteridae family. There are two similar species, Pteraster pulvillus and P. militaris, and identification is not straightforward. The first does not grow bigger than 4 cm and is recorded on depths from 15 metres. The latter should only be encountered deeper than 100 metres, according to literature. It can reach a diameter of 8,5 cm, though. The sea star I found had a diameter of 6-7 cm, so I recon it can only be P. militaris. This sea star obviously had not read the same literature as me, it should not be this shallow.

When I left the sea star, I had not much time to look for nudibranchs. Species no. 349 on seawater.no made the dive worthwhile, anyway. I was a bit cold after 75 minutes of diving, I must admit.

13. March 2011: The perfect scuba dive!

What is a perfect dive? There are of course many different answers to that question. I think most scuba divers will agree it needs to be a safe and controlled dive, but it has to be more than that, of course. I am always hunting for pictures of new species for my web site or improved images of existing species. Combine a new species or two with great visibility and a spectacular location, and we are getting there.

So, when Sven Gust suggested that I should visit the wreck of HMS Aston Villa, to look for the sea anemone A. callosa, I immediately saw the opportunity for a dive out of the ordinary. Both the wreck and the sea anemone were new to me. The British anti-submarine trawler HMS Aston Villa was sunk by German aircrafts on 1 May 1940, in Namsfjorden, Norway. The wreck starts at about 12 metres where a large boiler tank and numerous smaller pieces are scattered on the sea bed. Two large parts of the hull are lined up with the bow pointing towards the deep. If you plan for a 32 metres dive, you will get well below the bow. The anemone however, Sven told me, is a deep-sea species starting to appear at 48 metres depth, in the steep slopes just below the wreck. I heard his last instructions as I rolled over board: "Just continue in the direction the bow is pointing, and you will find it!" I know nature rarely gives any guarantees, but the sea anemones are not known as particularly fast swimmers, so I kept my hopes high.

Due to heavy snow fall the last days, the visibility was poor the first three metres. I started to worry. Will I be able to get an overview of the wreck? Fortunately, it cleared up as soon as I got below the fresh-water belt. A rope was tied to the wreck, so finding the bow was a walk in the park. It was a beautiful sight! I just love it, when a ship wreck actually looks like a ship, not just an underwater scrap yard. I knew I was going rather deep, so I saved the enjoyment of the view for the return. I swiftly passed the bow and saw steep slopes below, swept clean by winter storms. As I approached 50 metres some anemones turned up. Disappointment started to grow. Were all the preparations and logistics (using trimix and two decompression gases on such depths) for nothing? These were specimens of the very common deeplet sea anemone. "This was not what I was looking for, Sven!" I knew I had not many minutes to search at this depth. I turned north while slowly descending a few more metres. Suddenly, there were A. callosa all over the place! I apologize for the brief lack of confidence in you, Sven!

I pulled the camera into position and started to shoot. I rolled around the sea anemones, trying to catch them from as many different angles as possible. New sea anemones turned up all the time, and I tried to take photos of every one of them. This way I can record any variation in features like color or shape. Well back at my desk the following day, I counted 65 photos of A. callosa alone. After 20 minutes total dive time, I had to start the ascent. I tried not to waste any time before I reached the wreck. At 25 metres depth I slowed down a bit to enjoy the view. Although it was a bit dark, HMS Aston Villa was a spectacular sight. You sense the drama that went on 70 years ago, when the ship went down. Nature has started to claim the ship back, but the bow is a bit to deep for the winter storms to get hold of it. In stead, an Atlantic wolffish, had chosen to inhabit a hole in the deck. It looked good, but I had no time to take its picture. To avoid too long decompression, I had to continue towards the surface.

Returning to the rope, I was more than happy with the dive. I still had two options, though. I could continue to ascend along the sea bed, where I expected to find other photo objects during the decompression stops, or I could go along the rope, and probably not see much at all. I choose the latter, simply so Sven would see my bubbles and be confident everything was fine. The dive had lasted for 30 minutes, but I knew there was still 40 minutes of decompression ahead of me. I started to contract the strobe arms and regarded the mission completed. Seven minutes later, at 6 metres depth something I'd never seen before, came drifting towards me. It was approximately 4 cm and had a little red spot in one end and vivid orange tentacles in the other. It looked like some hydrozoan, but I did not know what it was. This was reason enough to restart the camera. I let go of the rope, keeping in mind that I had to stay at constant depth while aiming at the free-floater through the viewfinder. Some thirty shots later, I was content. It was time to ascend to the last decompression stop anyway. The day after, some googling in the net revealed it was a colonial hydrozoan called Physophora hydrostatica.

I expected the last and longest decompression stop to be cold (4°C water temperature) and boring. After another ten minutes the next little creature appeared. This time, I knew what it was, I had seen it once before. The little sea angel was less than 2 cm and I really did not have the right lens for the purpose. I had to give it a go, anyway.

Needless to say, when I returned into the boat after 70 minutes, a bit cold, but happy. I had just experienced the perfect scuba dive. It had it all, new species I had never seen before, a spectacular scenery, great visibility and a well executed diving plan!

Thanks again, Sven! You are the number one diving guide in these parts of Norway! :-)