■Visibility and Shooting Distance

The appropriate shooting distance depends on underwater visibility.
Visibility varies according to the diving environment, such as coral reefs, rocky areas, sandy bottoms, or muddy seabeds.

As a general rule, you can take a photo when the distance between the camera and the subject is within half of the visibility range. However, clearer and sharper images are obtained when you get closer to the subject.

For underwater creatures, the recommended shooting distance is usually within 1 meter. For people, the distance may be up to 3 meters depending on visibility conditions.

Shoot within 1 meter

Even in poor visibility, acceptable photos can be taken if you approach the subject within approximately 30 cm.

Effective within 30 cm

■Setting the Distance

Objects underwater appear approximately 25–33% larger and closer than they actually are due to light refraction.

Underwater objects appear closer than they are

Therefore, when using a camera that requires manual focus or distance setting, setting the measured (actual) distance may result in an out-of-focus image.

Adjust the focus based on how close the subject appears to you underwater, not the actual measured distance.