Future of Canister lights

[tbone1004]

The LX20 has quite an attractive price point ($600), and for good viz, I'd imagine that the lower power modes may be sufficient, would you agree to that? Did you mount it on a hard or soft handle?

For those interested, from the Dive Rite site:

Burn time

• High power: 4 hours at 20,000 LUX
• Medium power: 6 hours at 13,000 LUX
• Low Power: 12 hours at 7,000 LUX

For those wanting real ish numbers that mean something instead of lux.
high-1200 ish lumen
med-800 ish lumen
low-400 ish lumen

med is like a fresh 10whid, 1200 close to an 18whid for those that are curious

 

[stuartv]

For those wanting real ish numbers that mean something instead of lux.
high-1200 ish lumen
med-800 ish lumen
low-400 ish lumen

med is like a fresh 10whid, 1200 close to an 18whid for those that are curious

How are they getting 1200 lumens out of a single Cree XM-L2?

 

[tbone1004]

@stuartv the battery pack is big enough to overdrive it. It may only be 1100 with some big efficiency losses but those were calculated from burn time and pack capacity.

 

[wetb4igetinthewater]

For those wanting real ish numbers that mean something instead of lux.
high-1200 ish lumen
med-800 ish lumen
low-400 ish lumen

med is like a fresh 10whid, 1200 close to an 18whid for those that are curious

So your thoughts on: Scuba Lights and Accessories | Dive Gear Express®

Lumens, Lux and Burn Time - Caveat Emptor
Various LED dive light suppliers use different methods of determining light output, plus expressing them in different forms of measurement. What matters is the visible light from the LED that bounces off the reflector and passes through the lens. The quality of the reflector and lens, as well as the actual amount of power delivered by the battery have a major affect on the amount of light that reaches the target. Dive lights would be better described by the system lumens (sometimes called out-the-front or OTF lumens), which is the amount of visible light emitted by the entire system of battery, bulb, reflector and lens. Describing any LED dive light in terms of the radiant lumens specification of the entire light output for a raw LED module (including IR and UV wavelengths we can't see) at maximum power under laboratory conditions can be very misleading.

In our opinion, using lux measured at the target distance (typically 2 meters), and not just initially but across the entire burn time, is the best way to describe the brightness of dive lights. The difference is that the lux takes into account the area over which the light beam is spread. The lux is the visible light measured at the target distance, not the bulb. A light of 1000 lumens, concentrated into an area of one square meter, is said to illuminate that square meter with an brightness of 1,000 lux. However, the same 1000 lumens, spread out over ten square meters, produces a much lower value of only 100 lux.

There is a test standard (ANSI/NEMA FL-1, approved in 2009) for measuring flashlight lumen output, burn time and impact resistance. Sadly, we are not aware of a single dive light manufacturer who has elected to rate their lights using the FL-1 standard. Until they do, we must rely upon our supplier internally published specifications for our descriptions, but we suggest you take all of them with a grain of salt. Like the fuel economy ratings on automobiles, your results for light output and burn times may vary considerably from the questionable values being published by the dive light manufacturers.

 

[lucca brassi]

funny all producers now are smart ... three years before ..... no one did know nothing

but still what have standard ANSI/NEMA FL-1, approved in 2009 with diving lights ....

ONLY FEW THINGS because standard is written FOR HAND PORTABLE LIGHTS ON LAND!!

first of all test should be made submerged !

For instance almost all lights have thick front glass what data you will get on surface????
Or funny things when aspherics lens touch water without dry section ?!

Brains on hand please ! ..... If you can only COPY/PASTE
---------------------------------------------------
If you just know what kind of tests I have to made with automotive fuel pumps and other automotive sensors because costumers want tests and these tests runs 1/2 of year.... 24/7!

 

[tbone1004]

@wetb4igetinthewater

Lux has validity as that is what we observe. The issue with lux is that beam angle is very important to lux numbers and you can skew them heavily by using very tight beam angles. I.e. a laser has a very high lux level compared to the sun. Which provides better illumination?
If you compare a light with a 2* beam angle and a very small corona it will demonstrate a very high lux number but it won't actually illuminate a large area so it is not useful as anything but a signalling device. Proponents of very narrow beam angles often cite this as being important in water with high particulate content. Wide angle lenses in high particulate water will provide a lot of backscatter and limit your visual penetration abilities due to the backscatter. The issue with this logic is that you can only see so far forward due to the particulate no matter how tight of a beam you have or how powerful it is. At some point, you will be restricted by the particulate itself.
What is important is the ability to signal your buddy. In open water I prefer to dive within one kick cycle of my buddy, and in a cave, I just need the whole cave to dance. Lumens do that quite well. My primary light is a UWLD-35 which has a lot of critics because of the chosen beam angle. It is true that it provides a lot of backscatter during a siltout, but I have the advantage of being able to turn down the intensity to help mitigate that. In a silt out, my buddy is still able to see the two important signals which are "attention", and "trouble". Same signal, just different speeds. Doesn't matter if it is vertical or horizontal, just that the cave is acting like a disco ball and I need something so please come on over.
The advantage to that light is that it illuminates a LOT more of the cave than a really narrow beam of equivalent lumen output. This is important because the caves are pretty and I don't like the tunnel vision that HID's and the really tight beam angles give me. Many people disagree with that, but I just don't have that many things that I need to tell my buddy.
We use three and a half signals.
Attention-slow and deliberate lateral or vertical motion *I use vertical as it is more distinctive than what could potentially be a quick look at something that I thought I saw*. Stop, turn and look at me because I need you for something
Emergency-rapid motion of basically any direction. Stop, turn, come to me ASAP because I need your help NOW
OK-pretty self explanatory but a slow and deliberate circle. I start at the bottom, go up and around, and stop at the bottom. Usually repeat 3x if I am asking someone if they are ok.
OK and go that way-if I'm in the lead and it is a T, I will OK the intersection of the line and point down the direction that I want to go. My buddy will give an OK or an "attention" depending on if he agrees with the decision or not.

If vis has gone to sh!t for whatever reason, we are in touch contact so there is really no light signals. I get vertigo REALLY easily in siltouts, so as soon as I get on the line and in touch contact I close my eyes. I open them every once in a while to see if the vis has cleared, but I can't exit in a siltout with my eyes open. This is explained with any new buddies that if vis is less than about 5ft, my eyes are closed and I won't see any light signals. Probably not cool with the DIR crowd, but such is life.

 

[wetb4igetinthewater]

@tbone1004 ,

Thanks for the extensive write-up. So what I'm taking from this is that there are no clear standards for comparisons to be made, as everyone is going to present the numbers that make their products look best. Personally, I like some of the Halycon lights that are focusable with a knob on top. I have a 21w LM canister light, but I'm not a fan of light cords, and will sell it once I get around to earning a GUE fundies tec pass. At this point I'm weighting. Jim pointed out the DIve Right LX20's which for some applications, look like a great solution. But again, I'm still waiting until I have a need to justify a chance of what I have.

 

[tbone1004]

if you are looking at the LX20, I'd say to go and grab one of the Halcyon Flares. Better build quality, and an overall higher quality light. Bit less bright, but pretty snazzy. I'm also decidedly not a fan of the magnetic switches on the LX20. I think the Focus is too big for what it is and was done to mimic the size and shape of the HID's vs. making something that was a bit more space efficient.

The biggest thing though is to ask yourself what you are getting from those lights vs. diving with a higher powered backup light. If you aren't cave diving and need the really long burn time, is something that big and that expensive warranted?
Personally I'd take a pair of these, with light sock, 4x high end batteries and a charger for under $250 and call it a day. Sure the other lights are 30%-50% brighter and have 4x the run time, but does it warrant paying 8x the price?
Cave Adventurers - Explorer back-up lights - Marianna, Florida USA - Never Undersold!

If you're doing a lot of 60-90min cave dives and don't really do anything longer, then look at the Halcyon/Dive Rite lights with no question but I would say that you should try one of those and a UWLD on a try dive if at all possible to see if the really large/heavy light head is worth cutting the cord

 

[wetb4igetinthewater]

The biggest thing though is to ask yourself what you are getting from those lights vs. diving with a higher powered backup light. If you aren't cave diving and need the really long burn time, is something that big and that expensive warranted?

Which is why I'm waiting. I've only dipped my toes into tech. There are sadly not a lot of experienced instructors in the area. Fortunately, decompression and I have been chatting for him to come down to train me through the TDI system (I have AN/DP so far).

So until I have a real need to upgrade what I have (I do have the handheld focus, btw, but first gen) as I do need something to cut through the poor viz we have (typically 10-15 feet, give or take). I thought the Focus 2 would have the interchangeable batteries underwater, but either my memory is incorrect, or that got killed). So based on my slow progression in tech, I'm in no rush. It will probably be 2 years before I'm diving deep more consistently. 5 years before I get into caves (hoping to arrange something with Trace). I just am following trends for now.

 

[tbone1004]

@wetb4igetinthewater even with big deep trimix dives, remember that the vast majority of your dive time is going to be on deco where you may use the light for signalling, but that isn't enough to warrant going to a large canister. I.e. if I'm doing a deep trimix ocean dive with a planned bottom time of say 60 minutes but has a 3 hour deco, I'll probably want a 2 hour burn time on the light, but I definitely wouldn't say you need something with 4 hours on high. My lights get turned off during deco unless it's dark.
Even in the caves, I shut my primary off on deco and use my helmet lights on deco