8. Dec, 2019

The two golden safety principles for scuba divers are  ‘never dive alone’ and ‘always stick to your buddy’.   Here,  I’d like to briefly comment on these principles, focusing in particular  on some  drawbacks of buddy and group diving,   and conditions that may  rather spoil than enhance  the safety and  the peace  of mind of individual recreational divers.

The principle of buddy diving  First,  and most important   is  that a buddy system can  only be fully effective  when the buddies stay close to another,  and are  familiar with basic rescue operations when one of the couple gets in trouble. This could be a lack of air, getting entangled in a fishing line, problems with controlling the BCD or safety sausage,  etc.  Staying close to another,  maintaining regular eye contact and communicating with hand signals  are the crucial conditions to increase safety  of diving with your buddy.   Bob  Halstead once defined it clearly as follows: the buddy system is the situation which occurs when two divers of similar interest and equal experience and ability share a dive, continuously monitoring each other throughout the entry, the dive and the exit, and remaining within such distance that they could render immediate assistance to each other if required.  Murky water, darkness or  a  strong current may even necessitate the use of buddy line:  a line or strap physically tethering two scuba divers together underwater to avoid separation

On  recreational diving trips the buddy system often serves  as an automatic safety rule,  imposed by dive operators responsible for the safety of the group.  For example, divers that travel alone  are often coupled to new buddies, often with different experience or diving skills. To guarantee  at least the theoretical possibility that  they may assist  another when an emergency situation turns up.  When a diver is not able to stay close to his buddy, he is likely to be told to stay with the group  guided by a dive master. The guided group is a excellent option when diving  in more  difficult conditions such as  low visibility, strong currents, or when exploring new and photogenic  diving locations. Here the dive master often plays a useful role in pointing out nice subjects to macro- and wide-angle  UW photographers.

Solo diving and UW photography.  Often a diver carrying a  camera, may be the  lone camera diver in the boat. He or she will often experience the situation of being  left behind by the pack, moving faster that the photographer. This is even more likely to occur during  a drift dive, or when a diving group  is moving relatively  fast along a reef  wall or sandy seafloor. Obviously,  with  low  visibility such a situation will unevitably lead to loss of  eye contact with the group. The reason is that the  group does not allow the individual diver to linger behind.  Let’s  face it, it takes patience to get good shots, which is terminally boring for a buddy especially when he/she is not making pictures underwater. Such situations may cause tension for the UW photographer and group, and will necessitate a solo ascent for the solo diver using the sausage to signal the dinghy operator at the end of the dive. 

These situations, of course,  are less likely  to occur during UW photography workshops, where divers share  a common interest  and diving tempo,  and dive operators are more lenient in applying the ‘stay with buddy or group’  rule.

In my 40 year of diving, my best solo-diving experiences are the occasions when I went out  on my own in the early morning in my dinghy, to visit diving locations in the Mediterranean. I always selected familiar sites,  good weather conditions and viz,  with little chance of being disturbed by diving groups. Three lines with snap-hooks hanging  from  the safely moored boat allowed me hook up my camera, diving rig, and weight belt after the dive. In line with these experiences,  I’d like to end with another  Halstead quote:  Safe diving, from my personal experience, involves avoiding other divers underwater as much as possible so that I will not be troubled by their mistakes and being totally self-sufficient, with redundant systems, so that if even I make a mistake I can easily recover*.

* Of course not ruling out the more pleasant and safe forms of group diving.


Francis, John (19 October 2006). "Buddy System Breakdown". Scuba diving. Retrieved 15 October 2017.

Halstead, Bob (September 1997). "Assume the risk and take the blame" (PDF). SPUMS Journal27 (3): 153–4. Retrieved 10 November 2017

Layton, Rick (15 July 2012). "When The Buddy System Fails". DAN Europe. Retrieved 15 October 201





19. Sep, 2019

I am not qualified to provide an in-depth technical review of camera lenses.  But two interesting and relatively recent expansions of the  UW photographers toolkit seemed interesting enough to discuss here. The first concerns a (relatively) new Nikon fish-eye zoom lens.  The second the  Nikon new mirrorless cameras in the FX (full-frame) format.

Fish eye-zoom Fisheye lenses in  UW photography are superb lenses if you want to get really close to your primary target while keeping the background (e.g. the surface, other divers) in the same frame. Fish-eye lenses come in two versions:  the fixed focus prime lens and the zoomed fish-eye.  With the fish-eye zoom lens, you can change the focal length of the lens. It thus has the ability to take those forced perspective images at the shorter focal length or use a longer focal length to fill more of the frame. On a full-frame camera, it allows you to switch between frame-filling and circular fisheye. But the zoom lens is also useful to reduce its angle of coverage, for example, zooming in to fill your frame with a shark at a 2-meter distance, or with that small colorful fish at a 30-centimeter distance when using the CFWA  technique.

A popular example is the Tokina  AT-X 10–17mm f3.4-4.5 AF DX – a fisheye zoom lens designed for APS-C sensor cameras, which is also usable on full-frame cameras (see insert: top left). Then comes the newer (larger, heavier and more expensive)  Nikon-8-15mm fisheye lens (see insert: top right) that according to some recent expert reviews seems to be a must tot full frame underwater photographers. The lens produces excellent sharp pictures, great colors and offers a circular image at 8mm (floating in a black background)  as well as 180 deg diagonal view at 15 mm. The drawback might be that zooming in between  8mm and 15 mm, will show and cut off circle with black corners.  A circular view is not everyone’s favorite, but It can offer spectacular artistic images,  for example when taking over-under shots of a sunset above a coral reef.

This new lens can also be used on DX (cropped) sensors, like for example the Nikon D7200.  On the zoom ring of  Nikon 8-15 there is white marker placed at  11 mm, indicating  that with a cropped format the lens will work in the range between 11 and 15 mm: at 11 mm it will produce a 180 diagonal view and at 15 mm a 110 deg diagonal view (which is about the same range as the Tokina 10-17). At lower values than 11 values, the image will show a cut off circle with black corners. This is because the DX sensor is 1.5 factor smaller than that of a full-frame FX camera. So  10mm and 15 mm a  DX camera would be equivalent to 15 mm and  22 mm on a full-frame camera respectively. Will this lens also work in DSLR  housings for cropped sensors that accommodate the Tokina 10-17? I think it should, with the specific right zoom gear and dome port. My preference has always been the 5-inch minidome, allowing you to get very close to your UW subject. A  minidome is a half-spherical dome aligned with the nodal point of the lense.  

The question, of course, is if the new lens is worth the big investment of around 1000 Euro.  Some of us would say: only if it produces superior quality of pictures on a DX camera than the good old Tokina  10-17.  The ‘Tok’ is a much cheaper fish eye that for many years has been the workhorse for most cropped camera fish-eye adepts. As one of those, I am really looking forward to some comparative tests of both lenses on a D7200/D7500 camera. But see:   https://www.uwphotographyguide.com/content/first-impressions-nikon-8-15mm-fisheye-lens-review and https://wetpixel.com/articles/review-nikon-8-15-mm-f-3.5-4.5-fisheye-lens/P1

The advancement of the mirror-less cameras In the early days of mirrorless cameras, DSLRs simply did most things better. Mirrorless cameras were more compact and much cheaper, but that was it. Almost always, a DSLR could focus faster, shoot faster, had a much better viewfinder, and more often than not produced superior image quality. But with the increased quality of electronic viewfinders,  the much smaller weight and size and the bigger sensors the mirrorless camera seems to be gaining ground on the DSLR cameras, which make them no longer simply a more compact (but not always cheaper)  alternative.

Many UW photographers in the past including myself have been using the Nikon DSLR camera, either in the full-frame (FX) or cropped (DX) format. Nikon has been making some revolutionary changes by introducing the mirrorless Z6 (24megapixels) and Z7 (45 megapixels) full-frame cameras (see insert lower panel, to compare their size with the Nikon D850, explaining why the Z7 is also known as the 'mini D850'). When directly comparing the Z7 to the Nikon D850, the key drawbacks seem to be slower autofocus in low light settings, slightly less dynamic range, and shorter battery life. One of their best features is its high-resolution electronic viewfinder (EFV) making optical analog viewfinders (OVF) in DSLRs look ancient. While the OFV gives a view through the lens, the EFV gives you a view through the sensor and the option to present a lot of information.  The LED screen serving as an additional option to view the live scene, prior to or after your shot. In an underwater housing, the EFV image may still benefit a lot from a 45-degree viewfinder on the back of the housing (see:https://www.backscatter.com/reviews/post/Nikon-Z7-&-Z6-Underwater-Camera-Review).

The  Z mount has a larger diameter larger than the F-mount on the DSLR bodies and lies closer to the sensor because of the space saved by skipping the mirror.  When combined with an FTZ adapter the Z  will also take the new Nikon 8-15 fish-eye discussed above, and older DSLR  lenses, even those from the DX (cropped sensor, APS-C) range. Unlike with the DSLR,  the Z cameras will automatically apply a DX crop, so that the DX image always fills the finder. The latest AF-S (1984 - today) and AF-P lenses seem to work nicely. However, older DX lenses, like the 10.5mm fisheye will need a manual focus (according to the Ken Rockwell reviews). There are no tests yet of the performance of third-party fish-eye lenses, such as the Tokina. 

Nikon has just brought out an even cheaper mirrorless APS-C  (DX) camera called Z50 with an electronic viewfinder. Comparable to the D750 in resolution (20 megapixels),  but smaller and lighter and with a Z mount. No UW housings are yet available for this model. To use your old DX lenses, you again need the FTZ adapter.  So, Nikon will now be creating four separate lines of lenses: APS-C and full-frame for DSLR, and APS-C and full-frame for mirrorless cameras. So far, the big promise of the new mirrorless series is that they provide a lighter and smaller camera (allowing more compact housings, although the bigger lenses would mean an increase of weight and volume again) and a large bright electronic viewfinder, without losing much quality as compared with the DSLR full-frame Nikon workhorses. But some critics have argued that  Z-50 is is a mistake since you are not able to profit from the larger Z-mount with a smaller sensor. And that it will create extra costs because one needs to buy new lenses or an adapter for your old DX  (F mount) lenses.

 What to choose will become much more difficult for UW shooters in the near future. Since the cost of full-frame sensors has decreased dramatically over the last few years  a budget FX camera would compete head to head with a high-end DX camera


16. Aug, 2019

One of the most dramatic signs of climate change is the melting of ice in the Arctic ocean. Increases in temperatures and reductions in winter sea ice will likely affect the reproduction, growth, and development of krill and fish, leading to further changes in population sizes and distributions. A potential spin-off is that in northern Siberia and Alaska melting ice will create a richer banquet of nutritious ice algae. Although the melting ice is bad news for the polar bears, released ice algae, that live in water pockets at the bottom of the ice, are eaten by animal plankton, which in turn will become food for fish and squid, which forms the diets of narwhals and beluga whales.  

The other side of the coin is the impact of the imminent industrial exploitation of the Arctic. The melting Arctic ice offers great promises for the economies of superpowers China, the US, and Russia (see also my earlier Blog).  For cargo ships an ice-free Northern Sea Route is much shorter than the Suez canal,  to reach remote target countries.  For years, Russia has been using shallow-draft nuclear-powered icebreakers to aid shipping along the frozen Arctic waterways north of Siberia. But an ice-free passage for cargo ships is not the only promise. The exploitation of rich supplies of minerals such as gold and the immense gas fields by Gazprom is another.  Future drilling platforms and settlements along the coast of Northern  Siberia will need electricity. To fulfill this need, an enormous floating nuclear 70-megawatt power plant,  Akademik_Lomonosov,  equipped with two reactors is now ready to be towed towards the most northern ‘boom’ town  Pevek. Pevek is located about 14.000 kilometers north of the town of Murmansk at the polar circle (see small circles in the picture).  

And the foreseeing Russians want more.  Russia now claims the Lomonosov Ridge in the Arctic Ocean to be depart of part of the Russian Federation's adjacent continental shelf. The Ridge spans 1,800 kilometers,  about 200 kilometers wide, and divides the Arctic Basin into the Eurasian Basin and the Amerasian Basin (see the dashed area in the figure)  Russia formally submitted its request to the United Nations arguing that the shelf is an extension of the  Eurasian continent.

Some future investors feel that investing so much money in the exploitation of the Arctic continental shelf is a risky affair,  and there are doubts if the Northern route might be profitable in the longer term. Moreover,  in a period when the attitude of the general public and political arena moves toward reducing the negative environmental impact on climate change, exploiting the Arctic does not seem such a good idea. The presence of nuclear-powered vessels and power plants in the former pristine areas also creates risks for nuclear spills and might even lead to a ‘floating Tsjernobyl’, as environmentalists have warned.

5. Aug, 2019

Chimpanzee research in the United States started in the famous Robert Yerkes primate colony in Orange Park Fla in the 1920s. Yerkes groundbreaking studies primarily concerned the behavior and cognitive abilities of chimpanzees.  But in the 1940s, research at Yerkes Primate Research Center changed from behavioral to biomedical studies. The chimps genetic similarity  to humans was  the reason why chimps were used for  testing  for the toxicity of medical and non-medical substances,   the  search for the polio vaccine, and medications for tuberculosis, cancer, and hepatitis.#  

In 1986, the  National Institutes of Health (NIH)  started the Chimpanzee Biomedical Research Programs to study HIV and AIDS.  Hundreds of these primates received HIV injections in order to analyze how the virus develops into AIDS. Around the year 2000, there were about1,600 chimps in the United States being used for biomedical testing.  Some were owned by NIH, whereas others belonged to universities, foundations, and companies. A couple of years later it became clear that chimps were not a good model for human medical research since they are immune for diseases like HIV/AIDS, hepatitis, and the most common forms of malaria. Chimps also develop other forms of cancer than those affecting humans. They also do not develop Alzheimer disease, although their brain contains amyloid plaques like humans**.  The conclusion was that three decades of vaccine research using chimpanzees and other nonhuman primates has been startlingly unproductive. This eventually led the NIH to cease funding for HIV-AIDS research using chimpanzees.

 In 2000  the U.S. government effectively ended invasive work on chimpanzees and funding of this research and decided to retire chimps. Then in 2015— only 4 years ago today—the U.S. Fish and Wildlife Service classified all U.S. chimps as endangered, effectively ending biomedical studies on them.   Great Britain also quit granting licenses for the use of any of the four great apes as research test subjects. Other countries have since followed, including the Netherlands (2002), Sweden (2003), Austria (2006) and Japan (2006).  

In subsequent years the use of chimpanzees for medical research also raised increasing controversy because of their humanlike traits and genetic similarity. The more critical attitude was reinforced by publications by Jane Goodall on chimps in the African wilderness and Frans de Waal from the  Yerkes National Primate Research Center at Emory. Their studies showed an astonishing similarity between the emotions and social behavior of chimps and those of humans.  These new insights convinced many people that chimp biomedical testing was ethically indefensible.

But what to do with the enormous number of retired chimps in the US, once used for medical research? NIH declared that all of its approximately 300 chimpanzees would be retired, though it gave no time frame. Experts assumed that the remaining 340 or so in private hands would follow suit.  A law passed in 2000 created a national chimpanzee sanctuary, Chimp Haven in Keithville, Louisiana. The nonprofit sanctuary’s founders, who had worked with chimps in laboratories, felt that the highly intelligent animals—who, like humans, use tools, have some form of culture, and live in complex social groups—deserved to live out their lives in a setting designed wholly around their needs.

To date, still less than half (470) of the former 1000 lab chimps reside in sanctuaries,  Chimps Haven and Save the Chimp being the largest, while most of the other 577 chimps are still languishing in research facilities in suboptimal conditions (see *).  The happy and good news is that many middle-aged chimps -even after having spent many years in the confinement of research laboratories- when placed in sanctuaries have returned to their normal behavior and instincts, playing, grooming and even seeking ants in a termite hill***

#Other non-human primates frequently used in biomedical research all over the world are three species of macaques and various types of  Asian monkeys and baboons










6. May, 2019

Although it is now 36 years ago, in 1983,  when I started visiting the Sudanese Red Sea,  I still keep vivid memories of its splendid reefs and fish populations. Already 15 years prior to our visit a  British group called the Cambridge Coral  Starfish Research group had a field laboratory located on a platform of scaffolding built on a patch reef a few miles offshore from Port Sudan. Later the platform was also used by diver visitors from other countries.  Compared to their primitive accommodation camping on Sanganeb island offered a  more comfortable way to explore the Sudanese underwater environment, albeit from a more touristic angle of interest. After 1987, camping on the island was not permitted  anymore due to stricter military regulations

Traveling in that period was not easy: it often required a hectic chain of flights, like flying from London to Sofia, Cairo to Khartoum, and a 40 minutes local flight to Port Sudan. The tour operator was a small tourist agency in London, with a black-bearded Londoner named Jack Jackson serving as our dive master. The tourist agent in Port Sudan taking care of logistics, customs, etc.  was a friendly  Armenian Hamido, whose small office carried signed portraits of Hans Hass and Jacques Cousteau. It is said that poor Hamido once got lashed for selling beer to visitors.  A disused small marine transport vessel called Stormbringer carried us from Port Sudan to the northern Sanganeb lighthouse island (see insert: that was not our vessel!). Drinking disinfected water (no cold beer of course) and watching the lighthouse bundle circling against a starlit sky were some of the memorable moments of camping on the island. Two small compressors delivered our daily supply or air.  Our daily trips went to the South-West and  North points of Sanganeb,  or occasionally -with calm weather- to the more northern legendary Shab Rumi atol,  the location of the Cousteau's Conshelf II experiment in 1963. 

At  Sanganeb we must have been of the first groups that started baiting the grey reef sharks at the SW point, the most lively diving site. Here, a  sunny sandy plateau with coral heads at 20 meters descended rapidly to much deeper, cooler water.  Baiting was done by hiding a piece of smelly fish under a coral head or tying it to a rock. This occasionally caused much turmoil, with the sharks darting around, trying to get a share of the bait.  Occasionally groups of hammerheads (Sphyrna lewini) would be passing by in deeper water or sometimes moved in over the shallow plateau. Even more spectacular were the Shab Rumi (=Roman reef)  dives, where we met silvertip sharks at the superb south point.  Shab Rumi is also the place where one finds the gloomy remnants of Cousteau’sunderwater village with the mushroom-shaped garage of the underwater scooters at only 10 meters depth.   The Umbria (closer to Port Sudan) is one of the most famous sunken ships in the world. It is one of the jewels in the crown of Sudanese diving. At a maximum depth of 36m, the Umbria is shallow by most wreck divers' standards.  More to the North one finds the Toyota reef  (at Shab Su-adi) loaded with trucks, stranded in 1963.

Since its independence, Sudan has been ruled by a series of unstable parliamentary governments and military regimes. Under Gaafar Nimeiri, Sudan instituted Islamic law in 1983. This exacerbated the ever-living conflicts between the Islamic north, the seat of the government and the Animists and Christians in the south. The South became an independent state in 2011 but is since then torn apart by bloody conflicts between the two major tribes, the Dinka and the Nuer. In the Islamic North on April 2019, following stormy protests that faced fierce resistance from the Omar al-Bashir regime, the Sudanese military, under the command of Ahmed Awad Ibn Auf, took control of the nation and established the  Transitional Military Council that deposed al Bashir and dissolved the constitution. With the women's protest against their suppression by the regime as an important element of the resurgence in the streets of Khartoum. It will be an enormous challenge to establish a stable coalition to control this immense country, split up by various religious and ethnic groups. Participation of the more liberal Islamic groups seems a vital condition to accomplish this.

Currently, the best way to visit Sudan dive-wise is by live-a-boards departing from Marsa-Alam (Port Ghalib) in South Egypt or even directly from Port Sudan (e.g. Bluewater dive-travel). It might take some time, however,  before the travel and tourist conditions in  Sudan will approach the level of comfort and safety one finds along the Egyptian Red Sea coast. There are some signs in that direction, like the  Red Sea resort,  an alcohol-free, simple but clean accommodation 20 kilometers from Port Sudan. It takes divers to the nearby reefs such as Sanganeb and Shab Rumi. Expanding Red Sea diving to the Sudan reefs, to unburden the often crowded dive locations of the North and South Egyptian Red Sea would be a great opportunity for UW photographers in the future.