Handheld Primary Light (Cave)

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I'm surprised by that. I know it's 10 degrees versus 6. But, it's also 3500 lumens versus 1500. I still would have thought the HP50 had a brighter, as well as bigger, spot.



The LX20+ is 1500 on High. Why compare runtime on High instead of runtime when putting out 1500 lumens? It looked to me (my guess) that the HP50 would have a longer runtime when running at approximately the same brightness as the LX20+.

I couldn't find any info on whether either light stays the same brightness or gradually dims.

As the Dive Rite EX35 gradually dims, I figured the LX20+ and the HP50 would both work the same.

Do you happen to recall where you found info that the LX20+ stays the same brightness all the way until it goes into low power mode? (I'm inferring that's what you meant by "constant-current driver")
10 vs 6 is a massive beam angle difference. It doesn't sound like much but 10* is basically unusable in anything but perfectly clear water.
LX20 is constant output.
Output power consumption is non-linear and things can get a little weird when the lights go in the water, they do also have a reserve for when it kicks into low power mode and that's done based on voltage so it can trip a little strange. They also quote very conservative numbers, similar to UWLD, so you're always pleasantly surprised instead of slightly disappointed.
 
The Light & Motion lights are made here, so are Dive Rite's. The issue is getting flood and spot in the same light, most people don't do that for a reason....

HP50 vs LX20 is a beam angle thing. LX is 6*, HP50 is 10. 10 is a pretty useless beam angle IMO for most of the Florida cave systems. Too wide with the amount of particulate in the water but not wide enough for video.

Also, regarding lumens, and I'm talking real lumens like those quoted by companies like UWLD, Dive Rite, Light and Motion etc. with constant output drivers vs. bullsh!t claims about theoretical lumens like BB, Orcatorch, etc. I grew up in cave diving right as LED's were coming out where 10w HID's were the norm, those were about 700-800 lumen. @Capt Jim Wyatt grew up in the dark ages, almost literally where 200-300 lumens were a lot in the incandescent days so while I may own a pair of UWLD LD-40's and very much enjoy that amount of light, it is not unheard of for me when teaching to use backup lights on a goodman sock and even when diving with newer divers to just grab a backup light in the 700-800 lumen range or use my LX20+ on low or medium which is truly more than enough light for what you need. It gives you a completely different perspective on the cave

L&M is out. I won't buy lights with built-in batteries. And they don't make anything really bright anyway.

Dive Rite doesn't make any kind of video light, at all. They just have a "video diffuser" you can put over their light heads. I don't want a canister video light, so the EX35 is out. And, I would want a video light to be brighter than the HP50. So, Dive Rite is out, too.

So, what IS the reason people don't use lights that can do a fixed flood setting and a fixed spot setting in the same light? And, to be clear, I am NOT asking why photo/video pros don't. I'm not asking why serious borderline-pro level amateurs (aka prosumers) don't. That entire group does not come anywhere near comprising "most" of the divers that use dive lights.

My theory is that "most people" don't because, to "most people", a <$200 dive light is all they are likely to buy. Then, they'll get a GoPro and add a <$200 "video" light to that and now they have 2 lights for night dives, and they're good to go. So, they don't have combo lights because of budget and circumstances. For people in between - want better than a $200 video light, but don't want to spend $2000 on a single video light - why is a combo light a bad idea?

Also, for those inexpensive lights, they don't have much in the way of battery, so the light body is skinny and the light head is also skinny. Making a light like that with spot and flood ability would be a problem. Not enough room in the light head for all the LEDs and optics. But, when you start spending for a light with a higher capacity battery pack (like 4 x 18650 or 4 x 21700), then the light body gets fat. THEN, a fat light head that can do a spot out of a small-ish reflector in the center, and flood from an array of LED emitters around the perimeter becomes totally feasible. They're not High-CRI emitters, but for the use-case and price point, that shouldn't be expected. And is not really required.

Jim mentioned using his LX20+ on High in really huge passageways, and on Medium the rest of the time.

That makes perfect sense, to me. And the same logic seems to apply to a combo light - even in a cave. Swimming along in most passages, a "normal" spot light is fine. But, when I come into a big room, I might want to switch to a really bright flood light, just for the time I'm in there, so I see it (mostly) all at once. Being able to do that without pulling out a second light would be pretty convenient.... Only spending for one battery pack that can drive both use cases is also nice.

Having specific tools for specific jobs is great. Those tools do a better job than a multi-tool. But, Leatherman's do have a place in the world...
 
Most of the primary lights are perfectly adequate for casual Gopro use and any serious gopro users are probably going to want a tray with lights on arms which means true video heads. Those are also usually too big physically to put on your hand as a primary so you don't really want to wear them.
Too many compromises to make it do both so neither works as well as separate lights. The cost is low enough not to matter. If I'm helping friends with video work I just use a backup light on a soft goodman as my primary and I have real video lights. You'll figure it out with your use case how often you actually use the video mode vs. the primary mode and vice versa.
 
Most of the primary lights are perfectly adequate for casual Gopro use

That's the only thing I will really disagree with. I see GoPro footage all the time that is practically unwatchable because they were using a spot light. The video has a bright, blown-out spot in the middle where you can't see anything, and then whatever is in the spill you can see. Which means, normally you can't actually see the real subject of the video because the person with the spot light was shining it right on the subject.

I don't think pretty much any primary light is very good for even casual GoPro use. You either shoot with just ambient light, or you use a video (flood) light.
 
That's the only thing I will really disagree with. I see GoPro footage all the time that is practically unwatchable because they were using a spot light. The video has a bright, blown-out spot in the middle where you can't see anything, and then whatever is in the spill you can see. Which means, normally you can't actually see the real subject of the video because the person with the spot light was shining it right on the subject.

It looks like video where the spot light is searching for the aircraft in WW2 movies.
 
Yeah, the spec of 2:15 vs 3 hr doesn't make sense to me either. Certainly it will go past 3 on Med, but I haven't quantified how far.

Just a quick follow-up on this. The specs on their web page for the LX20+ appear to simply be wrong. The manual has different specs - the ones you'd expect to see.

In the actual manual, it says 4.5 hours on Med - i.e. half the output of High and double the burntime. And 9 hours on Low.

I speculate that the web page still has the stats for the older LX20 (non-plus) that is no longer made.
 

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