Nikon 1799 Subject is dominated by regular geometric patterns, AF-Assist Illuminators

Situations Where Autofocus May Not Work As Expected

Autofocus does not perform well under the conditions listed below. If you cannot achieve your desired focus using autofocus, use manual focus (x 61) or use focus lock (x 58) to focus on another subject at the same distance, then recompose the picture.

There is little or no contrast between the subject and the background.

Example: Subject is the same color as the background.

The focus area contains objects at different distances from the camera.

Example: Subject is inside a cage.

The subject is dominated by regular geometric patterns.

Example: A row of windows in a skyscraper.

The focus zone contains areas of extreme contrast.

Example: Subject is half in the shade.

The subject appears smaller than the focus area.

Example: Focus area contains both a foreground subject and distant buildings.

The subject contains many detailed elements.

Example: A field of flowers or other subjects that are small or lack variation in brightness.

AF-Assist Illuminators

If the subject is dark, a Speedlight with AF-Assist Illuminator can be used to assist the autofocus (x 153, 161).

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