Dive Lights - The Dive Otter

WARNING WARNING WARNING - THIS DISCUSSION IS NOT ABOUT LIGHTS FOR PHOTOGRAPHY/VIDEO

Primary vs Secondary

Generally speaking, divers will have one "big" light and one "smaller" light and they are called "Primary" and "Secondary". Technically, they can be exactly the same light if you wish, but often divers will use a more expensive "Primary" light and then a smaller or cheaper dive light as a "backup". An example of this would be:

OrcaTorch D720 : $350 (Primary)
OrcaTorch D710 : $130 (Primary or Backup)
OrcaTorch D580 : $40 (Backup)

Switch Types

There are all sorts of different switch types for turning the dive light on and off, however the industry has generally converged on two primary types: Screw-On and Push Button.

The primary deciding factor for which one to choose is do you believe it is more important to be able to turn the light on/off with one hand (Push Button) or is it more important that the light not turn on accidentally (Screw-On).

If you want the best of both worlds...

Primary is Push Botton ( OrcaTorch D720 or OrcaTorch D710)
Secondary is Screw-On (OrcaTorch D580)

Lumens vs Lux vs Candela

This is a holy war argument topic regarding lights in the dive industry. Does it matter? At a certain point yes. For the average recreational diver...no. There is not even a consistent industry standard used for measuring, so you can't even get an honest comparison across vendors. If you stay within the same manufacturer, the lumens will only really tell you if one light is "brighter" than the other. However, take a look below at the D720. It has a lower Lumen than the D710 but a significantly higher candela. I still don't understand lumen vs lux vs candela very well. For primary lights you'll generally want a lumen measure greater than 1000 with generally "more being better" unless you are looking for a tight beam like in the D720...then you'll want higher candela. The backup light should be similarly lumen'd but would be acceptable to be less.

Example:

OrcaTorch D720 : 350 Lumens / 425,000 candela / no lux given
OrcaTorch D710 : 1700 Lumens / 23,750 candela / no lux given
OrcaTorch D580 : 530 Lumens / no candela / no lux given

NOTE: the higher the lumens/candela the faster it will drain if the battery sizes are the same. The D720 and the D710 use the same battery. The D720 runs out at roughly 90 minutes and the D710 runs out at roughly 90 minutes. But have different lumen and candela stats.

Some dive lights, like the OrcaTorch D710 will show a lumen maximum of a huge number (compared to the size of the light) like 3000. Consider that like a "Turbo" mode...and it will only last a few minutes and not actually the level you will use. I consider it a marketing trick / gimmick.

And yes...some push button lights will have multiple lumen settings. That can be a pro and also a con. You have to click multiple times to turn it off as it steps down the lumens until off.

Beam Angle

* From STKR Concepts Generally speaking you want a tight beam angle unless the light is for photography/video work. This is for several reasons:

A tight beam angle is easier to communicate with
A tight beam angle is easier to control where the light shines...like not in your buddies eyes
A wide beam angle will increase the reflection back at you in water with lots of particles

Somewhere around a 6 degree beam angle will be just fine. If you have the funds for an adjustable light like the OrcaTorch D720 so you can have the best of both worlds..that's even better.

Storage / Placement

Every light should have a boltsnap attached to the back of the light. Here's a video from Circle H Scuba on how to do that. The light will come with a lanyard, throw it away.

Now that you have a boltsnap on the light, you can store/place the light like so...

Primary Light - Right Shoulder D-Ring
Secondary Light - Left Shoulder D-Ring

I've not heard/read exactly why in this order is the industry standard, but it would make sense to me if the reason is because your right hand is generally used less often than your left hand (SPG checks, BCD inflate/deflate, etc). And possibly because most people are right handed. Not sure.

But aren't they going to dangle and make me look like a "Christmas Tree"!?
Yup...unless....you add "snoopy loops" to your shoulder straps. No idea why they are called "snoopy loops"...they are just large rubber bands to snug the light against your shoulder strap so it's not a flappy snag hazard. You generally want a 2" diameter unless your shoulder straps (like on jacket style BCDs) are wider than normal.

Best Practice Procedure For Enabling

You would think the steps would be something like...

Unclip the light
Remove it from the "snoopy loop"
Reposition it in your hand
Turn it on

...but no...it's actually...

Turn it on
Unclip the light
Remove it from the "snoopy loop"
Reposition it in your hand

...because if you drop the light it will be turned on and easier to find.

But I want my hand free and the light turned on at the same time!

Which is why the industry invented the "Goodman Handle". There are Hard versions and Soft versions. Generally speaking the Hard versions are used for Canister Lights (see below) and the Soft version is used for the traditional flashlight style. There are literally hundreds of soft Goodman handles sold by as many different vendors....I prefer the one pictured to the right and sold by Cave Adventures.

The light is generally held in/on the left hand so that the right hand is free for emergency out of air procedures.

What Do I Do With the Light Temporarily During the Dive?

If you are not using a Goodman Handle, then the obvious answer is to just clip it back to the D-Ring from which it came. If you want it more readily available you can use your compass or wrist strap to attach the light so you can "drop" it out of your hand and pick it up again easily.

Canister Lights

Canister lights, though generally more powerful and longer lasting, have an altogether greater risk to you the diver as well your buddy and, in my opinion, should not be used by 90% of recreational divers. You can see a deeper dive on Canister Lights here. In short, the cord can trap your regulator hose(s) making an out of air emergency donation a cluster of tangled hoses. You also have to do more manipulations of the head of the light during otherwise routine activities which calls for situational awareness and pre-planning that is not often in the skillset of most divers. A canister light is generally "overkill" for 90% of recreational dives anyway.