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Under water, there is almost always not enough light for photo and video shooting. And if an underwater flash is the best solution for photography, then powerful flashlights with diffused light are used for video shooting, one of which we will test with the uncomplicated name A11.
Technical description from the manufacturer:
Light sources: 6 x white LEDs 9090 (XHP90) LED (max 20.000 Lm), 4 x red LEDs XP-E N3 (620 Lm) /610-630 nm, 4 x purple LEDs (390nm) /12W
Color Temperature: White LEDs: 5000K; red LEDs: 610-630 nm
Reflector: absent
Glass: 6mm polycarbonate
Body Material: High quality Type III hard anodized aluminum
Light Beam Scattering Angle: 120°
Batteries: 4 pcs. 18650 Li-ion, recommended for overdischarge and reverse polarity protection
Operating voltage: 2.8 — 4.5 V
Waterproof: 100 meters underwater
Dimensions: 122mm (length) x 50mm (battery box diameter) x 65mm (head diameter)
Weight: 450g (excluding batteries)
Indicator: blue color (100% -40% charge), red color (40% charge or less)
Packing and scope of delivery
The flashlight comes in a nondescript cardboard box with indistinct underwater photos as decoration. Packaging is «universal», because nowhere on it is the lamp model indicated.
The package includes the flashlight itself, a ball mount, a Goodman handle, a set of hex screws and some silicone grease in a bag. Batteries and charger are missing.
Constructive
The case in which the flashlight is made is quite common — it is used by many manufacturers. Only the composition and number of LEDs varies. The weight of the flashlight without batteries is 388g, which is 15% less than stated by the manufacturer.
The case is designed to install 4 protected 18650 batteries with a convex positive contact. Since the batteries are connected in parallel, it is possible to install a smaller number of batteries with a corresponding reduction in operating time.
The battery compartment is composite — a cover is screwed on the back, under which there is a contact pad that connects the negative contacts of the batteries. The lid is non-functional, and obviously appeared only due to the fact that the manufacturer was not able to make a solid body of the compartment. This is sad — an additional point of possible leakage. Although both threads of the battery compartment — both for the non-functional cover and for connecting to the head part, are well lubricated with silicone and equipped with two o-rings.
The head part of the lantern is non-separable. You can twist the bezel, but the glass cannot be easily removed, it is clearly planted on a sealant. Under the thick polycarbonate glass on a flat area there are 6 LEDs for the main light and 4 each for red and blue.
On the «head» there is also a flat platform with 3 threaded holes for attaching a handle or a ball mount. By the way, not a single through hole is provided on the case, so there is nowhere to attach a lanyard. This means that you can operate the flashlight underwater only with standard mounts, otherwise you will quickly lose it.
Both buttons are easily unscrewed with tweezers. Tightness is ensured by a single rubber sealing ring on a plastic thread, as well as a round silicone gasket between the button and the hole in the housing in which the microswitch sticks out.
Buttons are the weakest point of this flashlight design. The only sealing ring after a while begins to let water through. Gradually, the silicone gasket, which is pierced by the metal pin of the button, also becomes unusable.
A couple of years ago I had a sad experience of using a flashlight with this design (but with outdated LEDs), and the leak occurred precisely through the button. The lantern withstood a dozen night dives at depths of 10-20 meters, but then abruptly leaked at 25. After disassembly, the reason was established — the manufacturer “forgot” to grease the threads of the buttons, and one of them was missing (!!!) a silicone gasket. 4 expensive protected Imalent batteries were damaged.
But there is nothing fatal in these poorly designed buttons. Simple rules were simply confirmed that your diving equipment should be carefully checked after purchase, regularly serviced, checked for allowable pressure (pressurized). In this case, divers found a way out — a little lube, a piece of tape to prevent the button from “piercing” — and that’s it.
Unfortunately, it is not possible to test this sample during a real dive now, in coronavirus times. But for 3 hours in the pool at a depth of 6 meters, the lantern survived without leaks. Although 6 meters is only 0.6 atm of overpressure.
Operating modes
One of the buttons (left relative to the direction of the light beam) is responsible for switching white light modes, the other for red and blue light.
The main white light is provided by 6 LEDs, which are sometimes incorrectly referred to as Cree XHP90. The well-known manufacturer of LEDs CREE does not have such in stock. These are purely Chinese P9090 LEDs with unclear technical parameters)))
3 white light modes — maximum, medium and minimum. According to my measurements with a light meter, the average mode is 35% of the maximum, the minimum is 20%.
The manufacturer declares a maximum luminous flux of 20,000 Lm, according to my estimates, about 7-9,000 Lm. This (IMHO) is quite enough for night video shooting at a distance of up to 5-7 meters, especially when using two pieces on remote arms.
Emitting LEDs are fixed on the substrate almost immediately behind the glass, without a significant recess inside the housing. Therefore, the glow angle is 160-170 °, it is not clear why 120 ° are indicated in the technical data. The uniformity of the light field is very good, in my opinion. There are no artifacts like colored halos, blackouts, etc.
The second control button (right) is responsible for controlling the colored LEDs — red-red flashing blue.
As you know, as the depth of immersion increases, the red part of the spectrum gradually disappears from the daylight falling on the objects of photography. Therefore, at depths of more than 5 meters, photos and videos turn out to be more and more greenish-bluish.
The purpose of red light in such flashlights is to add a “cut out” part of the spectrum, giving the final image a shade familiar to our eyes. In fact, the benefit of such a backlight is doubtful, since the brightness is unregulated, so at shallow depths the red light is redundant and the final image turns red, and as the depth increases, there is a lack of power — after all, there are only 4 low-power LEDs.
Well, except that the mode of slowly flashing red light can come in handy in an emergency.
With the ultraviolet mode of operation declared by the manufacturer — a complete failure. It’s just blue. There is not even any talk of any declared 390nm. Security elements on banknotes, dirt does not glow. It’s a shame, because many varieties of corals and some inhabitants of the night sea fluoresce interestingly under the influence of UV light.
Operational features
There is no brightness stabilization, so the brightness drops along with the discharge of the batteries. There is no protection against excessive discharge of batteries. Therefore, in my experience, the flashlight worked continuously in the maximum mode for 60 minutes, while unprotected batteries with a capacity of 3400 mAh each were discharged to 3.02-3.04 V from the initial 4.18 V, while the brightness gradually dropped 3 times relative to the initial one. The medium mode, of course, is more stable — during the same time, the brightness dropped by only 20%, and the batteries were discharged to 3.66-3.67 V.
Temperature characteristics were also measured during this time. When being in still water with a temperature of 23° in the maximum brightness mode, the outer surface of the flashlight head did not warm up above 25°. Periodically, the flashlight was taken out of the water, unwound, and the temperature of the contact pad and batteries were measured. The maximum temperature did not exceed 28°
The situation is quite opposite when using a flashlight in the air. Even in the minimum brightness mode, after 20 minutes the temperature of the outer surface of the case reached 32 ° in the area of the battery compartment and 41 ° in the area around the buttons. In the maximum mode, after the same 20 minutes, the case warmed up to 47-58 ° and further measurements were stopped.
Thus, the operation of the lantern in the air is practically impossible, it is a purely diving lantern. You will either burn your hands or, if you use gloves, damage the flashlight and batteries.
In addition, in the air, the flashlight loses to «land» models in all respects — range, dimensions, weight, operating time.
Inconvenient, from my point of view, is that the main white light turns on immediately in the maximum mode and switches cyclically with a decrease in brightness. It would be better on the contrary — the inclusion in the minimum mode. The good news is that the manufacturer abandoned the main light modes that are absolutely unnecessary in my opinion — strobe and SOS.
The flashlight is quite weighty — 575g with batteries. Therefore, when using two or more lights in an underwater photo platform, you should think about compensating for negative buoyancy using carbon floats.
Pro Et Contra
» + » Wide, even light with enough brightness for underwater videography.
» + » Includes 2 types of mounts for the underwater photo platform.
«—» Impossible to use on land due to lack of temperature control.
«—» Unsuccessful design of control buttons, risk of leakage
«—» Lack of stabilization and built-in protection against polarity reversal and battery overdischarge.
«—» Impressive dimensions and rather big weight.
Outcome
The flashlight, despite the identified numerous shortcomings, can be quite successfully used for underwater video shooting, complete with an action camera and / or a camera in a box. You just need to remember to grease the threads, maintain the buttons and do not use the maximum brightness mode for a long time.
The flashlight can be purchased from the Banggood online store — LINK
When using a coupon BGY248 18% discount applies and price will be $69.69
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