I like the usb charging. It means less gear (of which there’s already plenty as a diver).
Good knurling and a strong loop, which you’ve already shown. Durable, waterproof build is a given, no need to comment on that.
I’d expect an ultra-simple UI, preferably on/off + double click for turbo (Turbo should be pretty decent given the cooling:)
21700 is the ideal cell size, given the increased capacity over an 18650.
I’d prefer a smooth reflector to OP, it would help cut through sediment often encountered when diving. Maybe offer both options as other might prefer flood.
Color-temp and CRI requirements will vary from one diver to another. I’d personally prefer the slightly better throw of whiter temp, but like Lux-Perpetua said, anyone exploring reefs, etc might prefer a warmer/high-CRI option
The Sofirn SD05 apparently has problems with corrosion when used for longer. The anodisation gets scratched and in salt water the aluminium starts to corrode. This is because the current passes through the flashlight body.
I would suggest to use an internal tube to pass the current from the tail to the head. If no current flows through the outer flashlight body salt water will not corrode it.
A triple or quad reflector with SST20 leds would be better than a SST40 or XHP50. 4000K 95 CRI should be awesome at a coral reef.
Not sure if it’s worth considering but some (optional) beacon light in the switch button or a phosphorescent / fluorescent GITD band might be useful if the diver suddenly drops his light while exploring a dark cavern.
For diving in low visibility, like here NJ shore I would like throwy beam with not too much spill. Visibility is usually about 15-25ft (5-8m) and lot of sediment floating around. Maybe TIR would be even better. 21700 is good for battery, about 1000lm output is enough. Two modes about 40% and 100%. CRI does not matter for me too much.
If you could fit blue or green laser operated by second momentary switch for signaling it would be useful.
For diving in clear water (Caribbean reef like) there are two scenarios.
Day time when light is used to look into all kind of holes and night.
At night you may want some more spill to see more around you.
That being said for me that would be a backup light.
Most of my diving is in Caribbean like water. And I think there is a lot of people that dive occasionally when on vacation and would like to have some photos from dive.
People who dive often in the area where they live (no issue with amount of gear because of luggage restrictions and such) are whole different customer group.
Pretty much on every dive I have a camera (small one since I don’t feel a need for professional setup with arms, dedicated light and such).
Because of that my most used light is Big Blue (something like VTL2600P – older version don’t remember model and if it was ever written on the light is gone now)
With that I can use only one light, using central LED with reflector like the lights above and have photo/video light as needed.
I have camera in one hand, light in another, with separate video light I would need to switch between them potentially using BSD pocket so not used one is not just hanging around on lanyard.
Personally I don’t find a use of red LEDs on such light. If anything I would prefer royal blue (bio-luminescence) but that just make UI much more complex.
Again 1000lm for spot is good, higher CRI not required, color preferably in 5000K range. Two modes 40, 100
For video two modes are ok for me, currently my light has 3 and I never use lowest mode. 40% and 100% sound about right. Hi CRI here also about 5000K. High efficiency COB or (edit:no COB, reflector is in the middle) multiple LEDs, more than 5000lm on high
For that one since it needs more juice I think I would be ok with 2 battery setup 18650 or 21700 side by side (head will be larger anyway) and personally I prefer it to be somewhat thicker rather than longer (easier to fit in BCD pocket, some pockets are pretty shallow and long light will stick out)
Maybe two switches to operate both modes separately or even turn them both at the same time.
General
No current passing thru the body, internal tube for one battery light or with 2 batteries side by side holder will solve that.
Thermal stepdown is ok but no timer of any kind (like some lights), thermal stepdown will help if light is used outside of water or turned on accidently , in water as long as there is good path between body and pill (LED, driver) there is no problem
Cut-off at about 2.8-3V for unprotected batteries maybe with some warning flash when close to it.
Good lanyard attachment.
I like USB charging, make sure is waterproof, i.e., does not leak into battery compartment if some water gets under cap. Would be better if light did not need to be open at all for charging (even if is slower) but that may be too much to ask. For small light most likely not feasible, for larger (this spot/video combo) maybe wireless charging (2 side by side body may be flat but that would require it to be non-metal, e.g., Delrin), maybe two exposed salt water resistant contact, reed switch inside and magnet in plug (so they are not electrically connected while underwater)
Stainless still bezel, smooth, no crenelation (I sometimes use light to bang on air tank, aluminum bezel gets damaged )
2h+ runtime on high
With 2 (or more batteries setup) it would be better to have them in parallel but I know it would be easier to work with higher voltage. Can be in series for 2 batteries.
So, for me there is plenty of these “backup” lights but if you can make that second and price is reasonable (I think less than $100 but may depend) I’m buying at least 2.
I agree regard use internal contact tube to avoid body corrosion in salt water,anyway still small compact size.
I also like have Red body color,simple ramping driver and triple/quad sst20 2700k(JA3).
But when for a small AA/14500 diving light?
Hi Fin17
I see you put me on the list. I never said I’m interested, I’m not if this is what it is. You asked about opinion of divers so I answered. I wrote if you make second one I wrote about I will be interested.
Also we still don’t know what kind of user interface it has.
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