By Ashok Kumar K
Everywhere in the world, nature photographers take millions of pictures of birds, animals, insects, flowers, etc. but relatively neglect one of the most colorful subjects of nature – fish and other marine creatures. If access to an aquarium is possible, wonderful photographs can be taken of these beautiful and fascinating subjects. This article explains the equipment needed for this type of work and in simple terms the technique to photograph fish and other creatures in an aquarium.
The equipment needed is:
SLR camera (preferably with automatic TTL flash)
Electronic flash (preferably dedicated) with diffuser
Off camera flash sync cord (preferably with TTL flash support)
Macro or macro zoom lens
Normal or wide angle lens
Black or deep blue paper or cloth
Flash meter (if TTL flash is not possible)
First the ambient light in the room should be minimum to avoid reflections off the front glass of the aquarium through which the photographs will be taken. If accessible, the backside of aquarium should be covered with black or deep blue paper or cloth (non-reflecting) to give a uniform uncluttered background. The front glass must be very clean inside and out. There should also be no floating particles in the water, as the flash will illuminate these, recording them on film.
Next is the important question of lighting. Most aquariums have lights at top. This lighting is however insufficient to allow the use of a fast shutter speed that is essential to freeze the moving subjects even when ISO 400 or ISO 800 film is used. Also the lights may result in colorcasts especially when using slide film. Hence the best solution is to use a light source in the form of an electronic flash. Generally when photographing, the camera will be at a distance from the aquarium and hence an on camera flash must be avoided, as it will cause reflection off the front glass.
Hence the flash should be put on an off camera sync cord (like SC-17 for Nikon). It should be held at the top of the aquarium pointed downwards with the flash head parallel to the surface of the water. If there is no access to the top of the aquarium (which is the case with public aquariums) the flash should still be put on a cord but held slightly to the top and left of the picture frame (area that is being photographed), pointing downwards and touching the glass to avoid reflections. Also the flash head should be covered with a suitable diffuser like tracing paper (or built in diffuser). Where possible, it is recommended that a table lamp is kept on the side to give a little illumination to see the subject and to make sure that it is in focus. Otherwise brighter ambient light is required raising the possibility of reflections.
The camera exposure mode must be set to manual exposure. It is best to set the shutter speed to the fastest sync speed the camera supports to avoid ghosting. The aperture can be set any where from f8 to f16. If the set up (camera plus the flash and off camera sync cord combination) supports automatic TTL flash feature then the camera will automatically control the flash output to get properly exposed photographs.
If the set up used does not support automatic TTL flash, then some experimentation or a flash meter is needed to find out the correct exposure. In this case the shutter speed can be set to fastest sync speed as before but the aperture needs to be set as per the experimental results or flash meter.
In all cases however the movement of the subject will not have any effect as the flash duration is extremely short thus freezing any motion.
Auto focusing is difficult in an aquarium and should be avoided, as it needs to track moving subjects resulting in focusing errors. So if the camera is an auto focus type it should be set to manual focus mode. It should be mounted on a tripod and pre-focused at a plane in the aquarium through which the subject will pass.
The choice of lens depends on what needs to be photographed. If the photograph needs to include a few creatures plus a bit of back ground, then a moderate wide angle like 35mm or a normal lens can be used. If close-ups are needed then a macro or a zoom with macro capability will be most handy.
A precaution that needs to be taken is that the front element of the lens should be parallel to the aquarium front glass through which the photograph will be taken (that is lens axis should be perpendicular to the glass).
After keeping the camera on the tripod the field of view of the camera can be marked on the glass of the aquarium with a glass pencil. Now with this set up, one should keep looking for the instant when subject appears in the frame that has been marked and release the shutter (through a cable release) when subject to be photographed is in the pre-focused plane at the right compositional position. This needs quick reflexes. The following explanation describes on how to find out if the subject is in correct focus. If it is a manual focus camera the image on the focusing screen will tell whether the subject is focus (sharp) or not. In an auto focus camera it is best to use the in-focus signal that is normally at the bottom of the viewfinder. This is the signal that will light up when the subject is overlapped by the AF sensor and is at the correct distance (in focus). Needless to say auto focus cameras with multiple AF sensors will be easier to use and they will also give more options for composition. A small aperture (at least f8) should be used to get adequate depth of field to eliminate any errors in focusing.
When using a macro lens the same technique can be used but reflexes (for releasing the shutter) should be faster since magnification is higher and hence the subject will appear to move faster when looking through the viewfinder.
Marine creatures, especially fish move constantly and hence are fairly difficult subjects. Hence it may take some time before the subject to be photographed comes to the right position. It must be remembered that the most important virtue that an aquarium photographer needs to have is patience! It may take hours before the right moment occurs. The next most important thing is practice as this improves reflexes. One should not get frustrated if the first session of aquarium photography does not give good results. Practicing a few more times will definitely yield truly beautiful pictures.
Suggestion regarding film: Marine life is very colorful hence a slide film with high color saturation (like Fuji Velvia or Kodak Elitechrome Extra Color) makes very attractive photographs. Of course print film can also be used.