Freshwater

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Part IV: Breeding and Other Fun Stuff
aperture is adjusted by a diaphragm inside the lens and is calculated in
steps called f-stops. You can see the f-stops available on an SLR camera on the
ring on the outside of the lens. The smaller the f-stop number, the less light
required, and the smaller the depth of field, or zone of focus. With fish photography,
you are usually working close up and with limited ability to provide
a lot of light, meaning smaller f-stops.
To get a large amount of the background in focus, you need a larger f stop —
or more light. The lens manufacturer usually supplies a table to help you
determine the aperture you need for the magnification you want. Or set your
camera to semi-automatic mode, if it has one, meaning you can set the shutter
speed to, say 1 ⁄60 of a second, and the camera chooses the correct aperture
automatically.
If your calculations point to an f-stop of 11, take one photo at f 8, one at f 11,
and another at f 16. This bracketing technique reduces your margin of error,
maximizes the probability of a useable shot. Keep a log of each exposure and
ask the developing lab to number your pictures so that you can gain a better
understanding of how each aperture affects your shot.
Larger lens openings (f 2, f 1.4) have a narrower depth of field (how much
area behind or in front of the subject will be in focus), which means you have
to focus more carefully. Smaller lens openings (f 16, f 22) have a larger depth
of field and require less focusing to get the correct image. Depth of field
increases with distance. The farther your camera is from your subject, the
greater the depth of field. Macro photos (extreme close ups of small objects)
have little depth of field because the lens is so close to the subject.
If all else fails, you can always have a photo studio crop your picture, which
entails having a professional cut out parts of the picture that don’t appeal to
you. Another option if you are not using a digital camera is to scan the image
into the computer using a scanner and then adjust it in your software. What’s
left is usually the shot that you were trying to get in the first place.
Composition Techniques
You need to organize all the visual elements into a balanced and appealing
scene in order to take good fish photos. All photos require a center of interest
(which is usually the most important image in the picture).
Obviously, most of the fish that you take pictures of are of some interest, but
other subjects in the aquarium can be accented by your aquatic pets. For
example, a piece of driftwood with an unusual shape or a brightly colored
castle can provide a center of interest that you can highlight by capturing a
small school of fish swimming nearby.