If you have ever been night diving, you know that a myriad of new and unusual creatures come out in the darkness that are normally hidden or invisible during the day. Octopus, squid, shrimp, and other invertebrates venture forth from holes and move freely about. Many kinds of fish show markedly different behaviors often allowing dramatic close up shots not possible during the day. For the macro photographer, this is whole new realm of abundant underwater photographic opportunities.
Nocturnal (active at night) animals in California include most crabs and shrimps and cephelopods (octopus and squid) and some species of fish. Moray eels forage at night, chasing their favorite food the octopus. Bright red scorpionfish come out to feed. Some kinds of rockfish move up into the water column, feeding mid-water in the darkness.
Being night active is not always a good thing for photography. Moray eels, for example, are generally easier to photograph in the day as they relax in the lairs. Octopus are the same, although you can sometimes get some unusual behavior photos at night. Squid and most shrimps, however, can only be photographed at night.
Animals that are diurnal (active in day) may be easier to approach and photograph close-up at night as they sleep. Garibaldi, blacksmith, sheephead and other fish tuck into the reef at night and often can be approached quite close. Other diurnal fish, particularly small ones, disappear from sight entirely.
THE CAMERA AND STROBES
Your normal macro camera rig will work fine so long as you consider the strengths and limitations of that system. You will most definitely need a modeling light to illuminate your subject material. Larger, more expensive strobes will usually have powerful modeling lights built in. Two strobes, both with modeling lights, are best to give your eyes a more accurate look at how your light will fall.
There are advantages, yet serious considerations, when using strobes with modeling lights. Strobes with strong modeling lights can double as your primary dive light, but you will still need to carry a back-up light, perhaps a medium-sized light that can fit in your BC vest. Modeling lights on strobes shorten the duration of battery life considerably. While a fully charged battery pack should last one, maybe two dives, a second fully charged battery pack per strobe needs to be on hand should more night dives be planned.
Also, while the modeling light(s) can be used to illuminate your surroundings and subject, they cannot illuminate your camera itself — important when you are trying to adjust settings on your camera. Headlights are particularly useful in for this application. A headlight will keep your hands free and give your camera the illumination it needs for adjusting various settings. Pelican and Princeton Tec make simple, inexpensive units. UK makes a small, inexpensive light that straps to your mask. More powerful units are made by NiteRider.
If you do not have strobes that have modeling lights, a supplemental modeling light can always be added to the strobe or strobes. Brackets on strobe arms can accommodate small lights or strap to strobe housings. Special brackets can sometimes be used to hold a light and slide into mounts normally used for viewfinders.
Obviously because you will be shooting in the dark, getting ambient light
in the background is not an issue. Use the finest grain film possible. Velvia is a good choice.
Take extra precautions against the cold. While water temperatures vary little between night and day, the psychological effect can be profound. Also, you will find when you are doing macro photography, particularly at night, you will be sitting very still on the bottom in a limited area. With little movement, you will generate less heat and you can get quite cold. Wear an extra layer of thermal protection.
Stay shallow, less than 70 feet; 50 feet is better. There is generally more small critter activity in this range and you don’t have to be as preoccupied with bottom time.
The night offers many new and exciting underwater experiences. Underwater photography, particularly macro, can be one fun and rewarding aspect of nocturnal diving.