How to equip underwater photographic equipment

Visual misjudgment in water, because of the refraction of light, the distance between objects in water looks closer than the actual distance 1/4, which makes the objects look bigger 1/3, and it is easy for photographers to misjudge the distance. If you use a camera system that needs visual focus, the safest and fastest way is to back off 1/4 and shoot again.

Change of color temperature Because of the different densities of water and air, the absorption spectrum is different from that in the atmosphere. When the water depth is about 6 meters, the red color has disappeared, and gradually the yellow color disappears at about 19 meters. The deeper the water, the higher the color temperature. However, since the light intensity will decrease with the water depth, it is not recommended to use a color temperature correction filter, but an artificial light source should be used to increase the light intensity and correct the color temperature, such as a flash. If it is not necessary to use natural light, it is recommended to shoot between 10 am and 2 pm. If the water depth is about 8 meters, it can still be corrected with CC 30R (the number of Kodak color temperature correction filters). If it is deeper, it is not recommended to use natural light sources. Of course, if it is a special artistic creation, it is another matter.

Suspended particles in water The light in water is atomized by the reflection between suspended particles, which will produce sharp photos. Especially when the flash is used, the phenomenon will be aggravated and even light spots will appear. Here are five suggestions: minimize exercise and avoid raising bottom sand; Try to get close to the subject and shorten the distance between the subject and the lens; You can use backlight to shoot silhouette pictures upwards; The middle layer of the water layer is clearer than the water meter and the bottom; Adjusting the flash to an angle of 45 degrees can not only avoid the refraction of light to the lens, but also simplify the background.

One of the charms of stable diving is the feeling of near weightlessness, which needs to be adjusted to neutral buoyancy under water. Therefore, underwater photographers will inevitably shake under the influence of water flow. When the current is too strong to stabilize the camera, we can increase the shutter speed, use a flash or improve the sensitivity of the film in exchange for image stability.

Thirdly, underwater camera system.

Can be divided into two kinds to discuss, one is itself a waterproof camera (U/W), such as Nikonos, Nikon RS and so on. The other is to add a waterproof shell to the general camera to achieve the purpose of waterproof. These two systems range from portable binocular cameras to professional monocular cameras. Before looking for a camera that suits you, you should know your own needs.

Ⅰ? 6? 4 waterproof camera series

Answer? 6? 4 snapshot waterproof camera portable camera is what most people call a fool camera. Most of these waterproof fool cameras have passive autofocus function on land, but most of them can only shoot with fixed focal length in water without autofocus function. The recent focus is mostly above 1 meter.

Advantages: low price, simple operation and light equipment. Because there is no focus, there is an underwater observer, which is convenient for observing the object being photographed. Most of them can also be used as all-weather cameras on land, and the autofocus function can be used.

The disadvantage is that it can only withstand the water pressure to the water depth of 10 meter, and only a few models can reach 45 meters. There are few functions, and most of them can't close up and adjust exposure value, so the system has low expansibility.

Common models Canon A- 1 and AS-6, Epoque ET- 100.

b？ 6? 4 rangefinder waterproof camera binocular camera with replaceable lens, because the observation window and lens are not completely consistent, the visual magnification, focusing and framing of underwater objects need to be corrected by experience.

Advantages: moderate price, special accessories that can be replaced (close-up, wide angle, etc. ), and fully functional. Some brands can even replace lens components in water.

Disadvantages: complicated operation. Even if automatic exposure is used to simplify the operation, it is still difficult to focus with visual judgment. In addition, when changing the lens, you need to add another observer to get the correct angle of view. Most equipment can't be used on land.

Common model Nikonos series, sea &；; Sea series.

c？ 6? The light of SLR camera enters from the lens, passes through the reflector and pentaprism and reaches the observation window. Therefore, the image obtained in the viewfinder is exactly the same as the image taken by the lens, and changing the lens or adding a filter will not cause the trouble of not being able to preview the effect.

Advantages: complete equipment and strong expansibility. The shooting angle and viewing angle are the same. It has auto-focus and auto-exposure functions.

Disadvantages: high price and heavy equipment. Can't be used on land, and can't be interchanged with land camera system.

Common model Nikon RS

Ⅱ? 6? 4 waterproof shell series

General waterproof shells can be divided into two types, one is made of metal and the other is a special hard plastic product. The camera in the housing can be operated outside the waterproof housing through the connecting rod device. The more connecting rods, the more complicated the manufacture, but the more perfect the camera function can be. We should give full play to the maximum function of the camera in the selection, of course, air tightness is also an important point that can not be ignored.

Answer? 6? Portable waterproof shell

Most of the advantages are that the instant camera is equipped with a waterproof shell, so the price is lower and the operation is more convenient.

Disadvantages are the same as portable waterproof cameras, but the optical quality is worse.

Ordinary model Ikelite aquashot

b？ 6? 4 Monocular reflex camera plus waterproof shell Monocular camera used on land generally, as long as it can find a matching waterproof shell. If they already have a ground camera system, this method is a good choice.

Advantages: complete equipment and strong expansibility. The shooting angle and viewing angle are the same. Most of them have autofocus and automatic exposure functions. High communication with land camera system, which will not cause repeated investment.

Disadvantages: the price is high and the operation is somewhat difficult.

Common models Subal, Ikelite, sea &；; Sea and other waterproof shell manufacturers mostly produce corresponding waterproof shells for the models of major SLR camera manufacturers.

The above underwater camera systems have their own advantages and disadvantages. Some shortcomings have nothing to do with underwater or terrestrial systems, which is actually the "fate" under this design. So before deciding which system to use, you must first understand your own needs and abilities. Here are a series of questions, hoping to help you understand your situation.

1. Key points of camera selection

A. The total weight of all your equipment, including camera, waterproof case, flashlight and flashlight connecting rod, can be controlled by you.

B. the purpose of photography. It is a general commemorative photo, a high-quality artistic creation or a record photo of engineering and ecology. These different purposes should be carefully considered in the process of deciding what kind of camera and accessories.

C. the camera system used by the potential partner. If you and your partner use the same camera system, you can use spare parts interchangeably. It has certain advantages in economy, equipment weight, maintenance and even experience exchange.

D. cost and time of maintenance. Including the length of the warranty period, whether it is safe, fast, and getting parts from the nearest maintenance point. Even if it is a discontinued model, you should pay attention.

E. the price of the product. Whether it is within your budget or not, don't forget to consider the price of necessary spare parts together. Comprises a special flash lamp, a special battery pack and a matching carrying case.

F. characteristics of buoyancy in water. Positive, negative or neutral buoyancy. It directly affects your activities in the water.

2. The key points of choosing waterproof shell

A. How many cameras can operate with their original functions? Such as auto-focus mode and auto-exposure mode.

B. appearance, weight and size. Whether in water or on land, it can be easily carried and operated.

C. whether the size and position of external joints are appropriate. For example, the joint of the flashlight connecting rod directly affects the difficulty of flashlight adjustment; The size and depth of the shutter release button affect the accuracy of pressing the shutter.

D. difficulty in disassembly and assembly of waterproof shell. This directly affects the maintenance of waterproof shell and the difficulty of replacing camera film, and indirectly affects whether it is easy to damage the joint due to improper wear or extrusion caused by difficult disassembly and assembly, thus increasing the possibility of water ingress in waterproof shell.

E. type and quantity of lens barrel (port). Different lenses should be equipped with different lens barrels, and the number of lens barrels represents the number of lenses that can be replaced. The material and accuracy of the lens in front of the lens barrel are the factors that directly affect the imaging quality.

F. characteristics of buoyancy in water. Contains all equipment, such as counterweight, flash lamp and its connecting rod.

G. is all the information easy to read? Of course, whether the camera information is easy to read is related to whether the viewfinder is designed at a high point, but at least there should be no dead angle, which makes it difficult to read the camera information and increases the trouble when shooting.

H. whether it is durable. How long you expect it to take is the key point to consider, but don't forget to test the life of the camera together. Especially now, various types of electronic cameras are eliminated quickly and minor changes are more frequent. It is recommended to buy the top model. Usually, this commodity has a long life, is not easy to be damaged and can be repaired quickly. Choosing a strong material can provide additional protection in case of abnormal operation or collision.

As for the waterproof shell made of metal and plastic, each has its own advantages and disadvantages, most of which are advantages and disadvantages. Because there are many camera models, the elimination speed is fast, and the production of waterproof shell models is also fast. If it is not matched correctly, it may be difficult to find one of the parts in the future. I believe there must be many underwater photography studios with various waterproof shells of early cameras. Either the camera doesn't match, or the waterproof shell is faulty but the camera is still intact. Simply put, the durability of the waterproof case is equivalent to the life of the camera. Of course, this refers to the general rules under all normal use conditions.