We asked our contributors what their favorite black-and-white underwater photographs were, and they came back with diverse and dramatic images and stories captured under the waves.

When it comes to responding to certain computer alarms, can one be too cautious? Being well informed about gas exposure limits and computer defaults can be an advantage. Simon Pridmore discusses a case in point, involving computer nitrox alarms on a routine wreck dive

Some ocean animals are just inspiring. To be able to glimpse a massive animal like a whale shark can be a lifelong dream that some divers never get to experience. The ocean’s largest living fish inhabits all of the world’s tropical waters, but sightings are usually rare. However, there are a few seasonal hot spots where the likelihood increases.