What is warned against when using a direct reading compass?

Using a direct reading compass requires confirmation with visual references to ensure accurate navigation. Relying solely on the compass without verifying with identifiable landmarks or other environmental cues can lead to potential errors. The underwater environment can cause distortion or misinterpretation of the compass readings, particularly in situations with poor visibility or when there are no reference points to guide you.

When navigating, visual confirmation helps to confirm the heading indicated by the compass, which is crucial for maintaining a correct course. This practice reinforces the reliability of your navigation and helps prevent disorientation, particularly in complex underwater terrains. Thus, not confirming with visual references undermines the effectiveness of your navigation efforts while using a direct reading compass.