I bought a pair of Sanniu “Bulb Flashlight” lanterns off of Amazon a while ago because they were quite cheap, and today I got around to opening one up.
These are cheap little plastic-bodied lights that come with a 3xAAA caddy, or can use a single 18650 cell instead. There’s one central LED behind a TIR (for flashlight mode), surrounded by 6 peripheral LEDs behind a diffuser dome (for lantern mode). There’s a magnet in the tailcap and a hanging loop, and the light comes with a carabiner.
If you really need a light and have nothing else, they’re not bad. They’re definitely a few steps above the dollar-store 9-LED lights in construction. I’ve had a few of those dollar-store lights literally break from putting on the tailcap — the battery caddy pushed the “driver”, LEDs, and lens out the front. This Sanniu thing feels much, much sturdier than that. Also I was extremely impressed that I couldn’t detect PWM on any of the modes. Cheers to the manufacturer for that.
But there are a couple of huge problems with this light for its (apparent) intended use for camping and such.
First off, the tint of all the LEDs is a very cool white. If I’m going to have a light hanging in my tent, I want it to a nice, cozy warm white. This is just way too cool, and not in a Fonzie kind of way.
Second, there is a mandatory blinky mode. You have one button, which takes you through the following modes (note that there is no mode with center and periphery lit up simultaneously, and the central LED only has one setting):
- Central LED (0.4A at tailcap)
- Peripheral LEDs, high (0.33A)
- Peripheral LEDs, low (0.08A)
- Peripheral LEDs, 2.4 hz blink
- Off
There are no shortcuts, and long presses of the button have no special effect. The instant you press the button it changes modes, and holding it down after the fact does nothing. If the light is on and you want it to be off, you can either cycle through the remaining modes (including the blinky) or unscrew the tailcap. If I’m in a tent about to go to sleep, I don’t want my light to start blinking when I go to turn it off, and I also don’t want to have to use both hands.
These might be worth modifying, though. I am particularly curious about the peripheral LEDs, and wondering if anyone knows anything about them.
Without further ado, some pictures.
The box:
The contents of the box:
Tailcap has a magnet, which could be stronger. It can support the light vertically just fine, but horizontal is rather iffy.
Here are the tailcap, 3xAAA caddy, and body tube (which, being made of plastic, needs a conductor strip running through it):
Here’s how it looks with the central LED lit up, then the periphery:
Here are beamshots. First is the central LED, showing how tight a beam the TIR produces. Next is the central LED overexposed to show how ringy the spill is. And then is the peripheral LEDs, with some artifacts that show up when white wall hunting but honestly aren’t that noticeable in actual use.
The diffuser dome on the head comes off without too much trouble, revealing an ordinary TIR in the center:
It also reveals the PCB, LEDs, and a SOIC-8 chip. The central LED looks more or less like what I’m used to, though it is on a shelf or pedestal that I wasn’t expecting, and is beneath a plastic dome (above and beyond any dome on the LED itself). Without disassembling it further, I feel like in principle I should be able to replace the central LED. But the peripheral LEDs have a shape that is completely new to me. Does anyone know anything about them?
Last but not least, here are some comparisons of the beam to a BLF-348. You can see how cool the Sanniu is.
Here’s a tint comparison between the BLF-348 and the Sanniu central LED. Note that the Sanniu is extremely over-exposed in this picture.
This is like the previous picture, but without the over-exposure. The Sanniu is much brighter than the BLF-348.
And here’s a comparison of the BLF-348 to one of the peripheral LED modes.
If I could make this warmer, and ideally get rid of the blinky mode, I’d like this a lot more.