Underwater communication with less noise and disturbance.
Underwater communication with less noise and disturbance. Underwater lighting is one of the clearest examples of how quickly technology can change what a practical configuration looks like.
What matters underwater
Tank bangers, metal pointers and shakers work, but they also add noise and hardware. Depending on visibility and team position, light signals, hand signals and a carefully used underwater laser can sometimes communicate more quietly.
The goal is not to outlaw familiar tools. It is to choose the least intrusive method that reliably gets the message across. Good communication begins before the dive when the team agrees what signals mean.
The practical point
The most useful light is not the one with the loudest specification sheet. It is the one that delivers the beam, runtime and ergonomics the dive actually needs.
Attention does not have to mean noise
Tank bangers, shakers and metal pointers can work, but I dislike creating unnecessary noise and I do not want pointing to become touching. My first choice is usually visual: move into the buddy’s field of view, use a torch signal, point with a hand or, historically, use a carefully controlled light/laser indication near a subject.
Any method has limits. Light can be invisible in bright conditions or when the buddy is facing away. Noise travels unpredictably and may annoy everyone. The best method is the one the team understands before the dive, not the loudest object clipped to the BCD.
Lumens are only the beginning
A torch can advertise a large lumen number and still be the wrong tool. Beam angle, candela/throw, colour, runtime, switch ergonomics, battery state indication, charging method and size all matter. One correction to a preference I have expressed over the years is worth making clearly: light output from multiple emitters can absolutely add together. What I often prefer about a strong single-emitter light is the beam character and apparent punch, not a claim that three emitters cannot sum to the same total lumens.
My own path went from modest lights, through Mares EOS models, to a compact Tovatec T3500S that became my favourite general torch. I like having enough maximum output for daylight holes, wreck details and signalling, while being able to run it lower at night. I also value direct charging and a battery indicator because those details remove unnecessary battery handling and guesswork.
Primary and backup lights are mission-dependent
For a simple daylight reef dive I may not carry the same lighting package I would take into an overhead environment. For technical or overhead diving, loss of light can become a serious problem and redundancy has to follow training and the plan. The broader discussion in my technical-diving torch article covers why a “bright torch” and a technical lighting system are not automatically the same thing.
Communication should be deliberate and non-intrusive
I dislike turning the underwater environment into a percussion section. Tank bangers and metal pointers can get attention, but I prefer visual signalling where it is appropriate. A light beam can be excellent. I also experimented with a green laser for pointing near—not at—small subjects and getting another diver’s attention. That experience was useful, but the DivePro L6 now requires an important safety caveat because a model recall changed how I would discuss or recommend it today.
My practical light checklist
I care about beam shape at the actual distance I will use it, switch behaviour with gloves, charge state before entry, realistic runtime at the output I expect to use, attachment and backup strategy. A torch can be extremely bright and still be badly suited to the dive if it is awkward to carry, impossible to read or short-lived at the required power.
Explore related topics
This article stands on its own, but these pages go deeper into the parts that connect directly with it:



