Photographing Fishes

Rudie H. Kuiter

Over the years I have been asked repeatedly about photographing fishes, especially since my article "Wild Tasmania" in Fishes of SahulV20-1, underwater, in the wild, as well as in aquariums. In principal there is no difference between photographing fishes in the wild or captive, other than that they are much easier to work with in the wild, particularly large fishes. Most difficult is photographing fishes that were just captured and getting good pictures of them before they change colour. Large fishes caught on line or in seines can be photographed by just holding them to have a record. For small fishes a small and portable aquarium is the best way, but various types of containers or even plastic bags that are clear can be used.



Getting good photographs of fishes in the field depends on a number of factors, but foremost knowing how to handle fishes, how they behave, and having a reasonably good camera. Let’s talk equipment first. For a camera, preferably use a SLR (single-lens reflex) and nowadays a digital SLR. There are plenty of choices for the latter and ideally it should have capability for interchangeable lenses and an external flash. My most often used lens is a 105 macro that goes 1:1 on film and about 1.5:1 on a digital camera. With film on the way out, digital is the way to go. For general photography fixed-lens digital cameras with a 5 or more Megapixel imager are fine too, but be aware of cameras with digital processed images that may be produced from small imagers that are generally much cheaper. For most publications, images from a camera with a 6 Megapixel imager are very good, but cropping is limited.

To get the quality shown in Fishes of Sahul, the pictures are at least 300 pixels per inch at the actual print-size. A 6 Megapixel camera produces a picture of 3000 x 2000 pixels at the highest quality setting. At 100 pixels/inch the actual size is 30 x 20 inches, or about 75 x 50 cm. The same picture at 300 pixels/inch measures 10 x 6.7 inches, or 25 x 16.7 cm, thus size is proportional to ratio. The final files are run through a distiller at 400 pixels per inch for the printing with a large number of dots per inch (about 2,400). Cameras that are set at 72 pixels per inch can look perfect on a computer monitor, but may be too small for printing. I now use a 10 Megapixel camera that gives me the option to do a larger degree of cropping.

SLR Or Not

With an SLR camera one looks through the lens via a small viewfinder on the back (usually) of the camera and your eye needs to be very close. Most people know of the digital fixed lens cameras with a nice large window to view and compose the picture. In general, these cameras are cheaper than SLRs, but there is an enormous choice and some are almost as expensive. The cheaper models may have macro facilities, but getting good results of fishes is very difficult, as it requires coming within a few centimeters of the subject. This is much too close to get a proper exposure from the flash. The more expensive models may have longer lenses to get some distance away from the subject so a flash can expose it, but I have not tried such a camera myself. The LCD on the digital SLR is only used for setting up the camera and viewing pictures taken. I find little other use for this screen. The LCD screen uses a lot of power, thus batteries are quickly drained if left on. When not using the screen, the battery in the SLR will last for months, depending on the lens and use of auto-focus. The batteries on the non-SLR cameras need regular charging.

Lenses & Flash

Ideally an approximately 100 mm long macro lens is used for small fish, but is usually expensive. Many zoom lenses can also do close-up, but good digital ones can be just as expensive ($1,000+). Zoom lenses, about 18-70 mm range, offered with a digital SLR camera as a kit and are a good buy, can fill the frame on a fish about 12 cm long. For sharp pictures and a good depth of field, so the subject is mostly in focus, a powerful flash is required. Built-in flashes are ok but have limitations and are too close to the lens when shooting through glass. Use the same brand of flash as the camera and use a small aperture for the required depth of field. When using a zoom lens, such as the one mentioned above, set it to the longest setting to avoid reflections from the glass. Hold the camera to shoot as straight as possible through the glass whilst the angle of the flash is less of a concern. If the lens looks through the glass at an angle it will create two slightly offset images, the offset-margin depending on the angle and thickness of the glass. When the glass is thin, it is less critical and a slight angle is not noticeable. If the flash is mounted on the camera, tilt the unit down very slightly to avoid flash reflections. If large fish are to be photographed (such as in a public aquarium) the flash may have to be held high above the camera with an off-camera lead. When using the digital TTL it is important that the flash and camera are at the same distance from the subject. The flash sends an undetectable short flash to measure the distance from the flash-unit (not the camera) to the subject and the system works out the appropriate exposure to shut the flash down when the required amount of light is reached. With film cameras the TTL works from the film-plane.

Handling fishes

Ideally, one goes diving in the same environment with the fish you want to photograph, rather then fiddling with setting up tanks to avoid reflections, etc. In general, fishes are easily approached, especially in freshwater, but diving is usually not practical. It comes down to handling or approaching fishes without scaring them, like any other form of wildlife photography. It is more difficult to catch fish and put them in an aquarium and expect them to behave or pose for a picture. So, besides a way to catch them that upsets them the least, some skill is needed to get these fishes to settle. When taking fishes home, one has time to settle them down, but when out in the field, time is of essence. I use a small aquarium that fits perfectly into an Esky with some bubble-wrap for transport and carry a few different coloured pieces of plastic that I can put inside the tank for a background. The aquarium is put on top of the Esky and preferably set-up in the shade or under cover. I normally use the same water from whence fish were collected and, if needed, cover the bottom with sand, gravel or stones from their habitat. Put some fish in and let them settle down, be patient. Of course the glass of the aquarium needs to be clean and prepared before putting the fish in. Take a few pictures for practice once the fish are settling down.

If the water is dirty, take pictures only when the subject swims near the front of the aquarium. The plastic backgrounds I use are about 2 mm thick and slightly longer than the aquarium, thus have to be bent to fit inside the tank. This also holds it in place and I can put it from near the back to the front, where required, sometimes to restrict the fish to the area near the front. Active swimming fish don’t like to be enclosed and given some space, at least so they are able to turn around. I found it best to use a dark background with dark fish and a pale background with pale fish, but sometimes I do both. Avoid strong contrasts between subjects and backgrounds. If not familiar with exposures, experiment with compensation. Fishes such as rainbows often have a silvery ‘ear’ spot that may cause burn-out on some digitals and may need to be compensated for, up to minus-1 or even minus-2 stops on the earlier model cameras. This may make the general picture dark, but this can be fixed with computer software. With digital, take lots of pictures if not sure and use different settings. A powerful external flash is essential and provides a good depth of field and, when having to work in strong ambient light, to avoid blur from movements. Most camera manufacturers have external flash units with TTL facility to provide perfect exposure. I like to aim for the highest F-stop to get maximum depth of field (when desired) and I normally shoot at F16 to F32 when filling the frame with the subject from 15 cm to 30 mm fish respectively, and if the subject has general colouration. The high F-stops also help eliminate problems caused by strong ambient light. When I was in Tasmania I had to work in bright sun-light and could see myself reflected in the aquarium. Dark clothes are best suited for this work, but can make you hot.

General hints and Summary

Digital photography is very forgiving, unless one over-exposes the subject. Default settings are usually fine and when new to digital, use these first. Films have a sensitivity expressed in ISO, and 100 or 200 ASA are most commonly used. The sharpest pictures are achieved with slower film and with digital the lower setting is for best quality. With digital SLR cameras, one can select the sensitivity from one picture to the next - that is very useful when shooting with natural light. When light is low, higher ISO provides more speed, but, like film becomes grainy, digital images create noise. This is visible in dark areas as tiny green or red spots, but with a good camera you can go quite high and get good results. Once getting used to the camera, and venture into the custom settings, take it slowly. It can be a bit overwhelming with the many options. White Balance, colour temperature, file types, etc. Shooting quality and getting the exposure right is what is most important. I use the fine and largest file option and work the exposure compensation where required. I found no advantage in using RAW (usually asked for by photo-agencies) versus Jpeg. RAW files use a lot of storage space and converting them to something useful is like film-processing. I have worked with files of Nikon, Pentax and Canon, and the camera processing to Jpeg is usually very accurate, but I found Canon Jpeg files often reddish compared to RAW. Usually the processing by the camera, converting to Jpeg, is excellent, so why not use it? The main thing is to get the exposures correct and I often purposely under-expose slightly. Colours can be corrected later. White areas against a generally dark background may show ‘burn-out’, meaning an area with no data - pure white. The latest cameras have much better control of this and I found in some cases the compensation is overdone, changing the default setting to one that suited me better.

I found the Auto setting of the White-Balance good for most work. Water, such as running in rapids may go a bit too blue (cyan) and there is a setting for Flash when using external flash that gives slightly better results compared to Auto; however, this colour is easily corrected in software programs such as Photoshop (Image>select>colour>cyan). Whilst Photoshop is a wonderful tool and beats working in darkrooms, one can easily overdo things and what is shown on screen does not necessarily match a printed file. Normally pictures are produced in a mix of Red-Green-Blue (RGB) that look perfect on monitors that produce an image from the same mix, but printing is done from colour separations, usually in Cyan-Magenta-Yellow-Black (CMYK). When viewing a CMYK file on screen it is a conversion back to RGB. The CMYK colours vary between different kind of inks and each printer has its own conversion formula and some Inkjet printers have additional colours to get better toning. Printing is done in dots along lines and has no relationship with pixels. Good printing, maybe with 2400 dots per inch and hundreds of lines per inch, thus a pixel, that is square, may be represented by 8 x 8 round dots. On an inkjet the ink spreads enough to join the dots, giving it a photo finish, but when printing on a commercial machine it is different and the dots are more defined. Check a picture in Fishes of Sahulwith a magnifier and the pattern can be seen. The machine on which our magazine is printed also has RGB conversions, but when this mode was used many pictures went dark (the volumes prior to the ones printed by Mercury Printeam). Preparing the files in CMYK has taught me that the best results are achieved by doing all the colour corrections in CMYK. The only corrections I do in initial RGB files are getting the brightness of shadows and highlights correct.

This brings me to photographs submitted for Fishes of Sahul. The maximum size of the printing of a file is determined at 300 pixels per inch. The can be checked in Photoshop (Image>size). If you need to change it to 300 pixels/inch, change the measurements in such a way that the file-size in Megabytes remains about the same. Do not create a bigger file, as this can have horrible effects on some aspects of the photograph when compression is used (Jpeg, Eps, etc.). However, depending on subject and background matter, I can sometimes do slight improvements and can increase pictures marginally. Best is to supply pictures as they are, as long as they are of reasonable size and quality. Some pictures that were supplied at 72 pixels per inch for previous articles could only be produced at a small size to still look good (less than 1/4 page). If taking pictures intended for use in F.O.S., use the fine or large settings, especially on the simple cameras. It reduces the number of pictures available dramatically and storage needs to be taken care off. A cover shot, for example, measuring 155 x 109 mm, at 70% is a 26 Mb file (=3.8 Mb high quality Jpeg). Files are preferably 10 Mb or bigger as a Photoshop of TIFF file or 1.2 Mb Jpeg highest quality.

Preferably do not use sharpening, stamp-tool or any other Photoshop tools. Undesirable spots, glass scratches, distracting background matter etc. will be removed when preparing the images for use in the magazine. The magazine is a semi-scientific journal and fish can not be tampered with, other than minor repairs on fin or body damage that will not interfere with its morphology. Colour will be optimised in a realistic way (as the images shown in Fishes of Sahul). Pictures can be supplied as film (negative or positive) or digital files on CD.

If you would like to discuss further or wish to ask any questions, please do not hesitate to contact me as follows:

Rudie H. Kuiter
Email: rudiekuiter<at>
Phone: 613 (03) 9766 4074
Postal: PO Box 124,
Seaford, Victoria, 3198