Max. luminous flux
The maximum luminous flux provided by the lantern.
Luminous flux (denoted in lumens) can be described as the total amount of light produced by an LED or other light source and distributed in all directions where this source shines by itself (without lenses, reflectors, etc.). In fact, this means that the capabilities of the flashlight depend not only on the luminous flux, but also on the angle of illumination (see "Angle of illumination (light)"). For example, a relatively weak stream can be concentrated into a narrow beam, providing good range; and a
large number of lumens will inevitably be needed to effectively cover a wide area.
Note that the coverage angle is not always specified in the characteristics, and even with such data it is difficult to immediately assess the real capabilities of the flashlight. Therefore, for such an assessment, it is best to use information about the actual illumination range (see below), and also take into account the general type of device (see above). For example, for the same number of lumens, a handheld flashlight with a reflector to form a directional beam will give a noticeably greater range than a tourist lamp with 360 ° coverage.
It should also be borne in mind that the
high brightness of the flashlight is far from always justified, and it is worth choosing according to this parameter, taking into account the actual conditions of use. S
...o, when working at short ranges, bright light can become a hindrance: it tyres the eyes and can blind others. In addition, an increase in brightness usually requires more powerful sources of both light and power, and the weight and dimensions of the lantern increase accordingly.Lighting range
The maximum range at which the flashlight provides any effective illumination of objects. Different manufacturers have different criteria for this efficiency when measuring ranges, and therefore it is only possible to unequivocally compare among themselves in range only models of one manufacturer. At the same time, this parameter allows us to compare models from different manufacturers with some certainty: for example, flashlights with a lighting range of 15 m and 100 m will clearly belong to different range classes, regardless of manufacturers.
Note that the range of illumination depends not only on the maximum luminous flux provided by the lantern (see above), but also on the features of its design: the narrower the beam is provided by the reflector of the lantern, the greater the range will be, and vice versa — scattered light does not spread far. Some models allow you to adjust the beam width depending on the requirements of the situation (for more details, see "Adjusting the focus").
It is also worth bearing in mind that models with the same claimed lighting range can cover different spaces. For example, a hand lamp (see Type) with a reflector diameter of 20 cm will be able to provide a wider beam than a conventional hand lamp with a 5 cm reflector. And although in both cases the objects that fall into the light spot will be illuminated in the same way, however, in the first case, the size of the spot itself will be larger, and the actual efficien...cy of the flashlight will be correspondingly higher (in light of the fact that it is easier to "feel" individual objects with a wide beam, especially at a considerable distance).
Focus adjustment
The ability to adjust the angle and range of focus the beam of light provided by the flashlight.
With the same value of the light flux (see above), a narrow beam covers a small space, but allows you to shine far and illuminate objects more brightly (because more light enters per unit area). As the angle increases, the range and apparent brightness of the illumination decreases, but the flashlight provides simultaneous illumination for a larger area.
Focus adjustment allows you to choose the necessary option from these two (or even some intermediate one), depending on the current situation.
Max. operating time
Maximum runtime of the flashlight without changing batteries or recharging the battery.
Note that in models with brightness control, this time is indicated for the most modest and, accordingly, economical mode. For example, in a flashlight with a maximum luminous flux of 1000 lm, the claimed operating time of 20 hours can be achieved at a brightness of only 30 lm, and at maximum battery life may not exceed half an hour. These nuances should be clarified according to the detailed characteristics. However, also note that additional modes of operation (see below) are not taken into account in this case: for example, if the flashlight from our example in SOS mode can operate for 30 hours, the characteristics will still state 20 hours.
It is also worth bearing in mind that for models with replaceable batteries, the actual operating time will also depend on the quality of such batteries. For example, for flashlights for AA and AAA elements, battery life is most often given when using high-quality alkaline batteries; if instead of them inexpensive saline ones are used, the operating time may be several times shorter.
In general, when choosing a flashlight according to the maximum operating time, it does not always make sense to focus on “long-playing” models: they often have either low power or impressive weight / dimensions, and the price can significantly “bite”. Flashlights with a long battery life will be useful first of all to those who have to s...tay “away from civilization” for a long time: extreme tourists, rescuers, military, etc. And for most everyday tasks in a modern city, and even for trips to nature for several days, up to 10 hours is enough.
Brightness levels
The number of brightness levels provided in the flashlight design. Most modern models have one level of brightness, but there are models with the ability to adjust.
Several levels of brightness allow you to choose the best option for a particular case: for example, to view a small room, you can reduce the brightness and save battery power, while in a large warehouse you may need full power of the flashlight. Accordingly, the more brightness levels are provided in the design of the flashlight, the wider your options for choosing the best option will be.
Also note that in addition to step-by-step brightness adjustment, with fixed levels, modern flashlights can also be used with smooth adjustment. It is detailed below; here we note that the stepped format is technically simpler, cheaper, and therefore is used much more often. And in individual lamps, these options are combined — for them, the characteristics indicate both the number of individual brightness levels and the presence of smooth adjustment. The specific way to implement such a combination may be different. For example, a brightness control ring can have several fixed levels with clear values, and the ability to set any intermediate position between these values; the main mode of operation with smooth adjustment can be supplemented with a fixed level of reduced or increased brightness; etc.
Power source
The type of batteries used in the flashlight.
The most popular nowadays are replaceable cells in sizes AA, AAA,
C,
D and
CR123, replaceable lithium-ion
18650 batteries, as well as
branded batteries. At the same time, some models from the latter category are designed for standard batteries for power tools and are supplied without their own power sources at all; such devices are commonly referred to as the so-called
building lights. And here is a more detailed description of the different types of food:
—
AA. Batteries, colloquially known as "finger-type" batteries. One of the most common sizes nowadays; such cells are available both as disposable batteries and as rechargeable batteries, and they are sold almost everywhere. On the other hand, in modern flashlights this option is less common than the more miniature AAA — the development and reduction in the cost of LEDs has made it possible to effectively use more compact power supplies.
Note that "finger" batteries can vary markedly in capacity; accordingly, the battery life of a flashlight with such a power supply will be different — depending on the brand of batteries (accumulators) used. Also note that the use of such cells (like most replacement batteries) is inevitably associate
...d with additional expenses: you will either have to regularly buy fresh disposable cells, or spend money on a set of batteries with a charger.
— AAA. They are also "little finger" batteries — by analogy with the "finger" ones described above. They are also available in different formats — both batteries and accumulators — and in different capacities and prices. They are smaller than AA, which is why they are generally inferior to them in terms of capacity. On the other hand, modern LEDs often have enough of such power; and compactness is often more important than high capacity. Therefore, AAA elements in modern flashlights are much more common than AA.
— C. 1.5-volt cylindrical batteries with dimensions of 50x26.2 mm; approximately equal in length to AA, but much thicker, due to which they have a much higher capacity. Some time ago they were quite popular, but now they are used extremely rarely — mainly in devices where the dimensions of the case initially allow the installation of such power sources (a typical example is batons, see "Type").
— D. Cylindrical batteries, the largest (61.5x34.2 mm), capacious and powerful among the currently used 1.5-volt power supplies. Similar to the elements of type C described above, they are rarely used, mainly in lanterns that initially assume large sizes.
— CR123. Cylindrical batteries. They have a length of 34.5 mm and a diameter of 17 mm, due to which they resemble a smaller variation of type C, but differ in operating voltage — 3 V. In the battery version, they are marked as CR123A. In general, they are quite rare, mainly in hand-held compact models and key chains, as well as underbarrel flashlights for pistols (see "Type"); however, specifically among these categories, such batteries are quite popular.
— 18650. In general, nowadays, a whole family of batteries is produced that use a 5-digit marking — for example, 14500 and 17650. All of them are made using lithium-ion technology, and have a cylindrical shape and a voltage of 3.7 V; the marking indicates the dimensions of such batteries in diameter and length (see below for more details). Specifically, 18650 (diameter 18 mm, length 65 mm) is the most popular type of such elements — both in general and specifically among flashlights. This is primarily due to the combination of compact dimensions and fairly solid performance. At the same time, thanks to cheaper technologies, 18650 batteries can now be used even in low-cost models — including those initially supplied in the kit. However, anyway, it would not hurt to clarify the complete set of a flashlight with such a power supply separately — and this applies to both the battery and the options for charging it available “out of the box” (for more details, see “Packaging”).
In general, such elements combine the advantages of replaceable batteries and branded batteries. On the one hand, the power source is reusable; when the charge is exhausted, you do not need to spend money on fresh batteries every time; on the other hand, if desired, you can purchase several batteries and quickly change them as needed. And with a separate charger, you can completely reduce work interruptions to zero: while one set of batteries is in use, the rest can be charged.
— Accumulator. This option means that the flashlight uses a branded battery that does not belong to standard sizes (and in many models it is also non-removable). One of the advantages of such a power supply is that the user does not need to spend additional time and money on buying batteries: the power supply is initially supplied in the kit, and when the energy is depleted, it is enough to charge it. At the same time, the delivery set may include both an adapter for an outlet and a car charger (for more details, see "Packaging"). The second advantage is that branded batteries are often more compact and at the same time more capacious than replacement batteries; and in general, such a battery is easier to fit into the design of a flashlight (especially non-standard). Among the key disadvantages of this option, first of all, the impossibility of a quick replacement can be noted — usually, a dead battery needs to be charged, which takes time and a power source. In addition, having your own battery inevitably affects the cost; this is especially noticeable when comparing low-cost models of rechargeable flashlights with battery-powered counterparts. However, the difference in price can quickly pay off with intensive use.
A special case is the so-called "construction" rechargeable lights. They are produced mainly by large manufacturers of power tools (Bosch, DeWalt, Makita, etc.) and use replaceable batteries for tools of the “native” brand as power sources. At the same time, such a battery is usually not included in the kit — it is assumed that it is more convenient for the user to buy a battery on their own, at their discretion (or that the household already has a branded tool and, accordingly, a power source).
In addition, more rare and specific food options can be found in flashlights:
— AAAA. Batteries are even smaller than the "little finger" AAA — 43 mm in length and 8.3 mm in diameter. They are used in some thin compact format lanterns, many of these models resemble fountain pens in shape and size.
— Replaceable Li-Ion batteries with a 5-digit digital marking — similar to the 18650 described above, but differing in size. Specifically, among the flashlights you can find the following form factors of similar power supplies: 10180, 10440, 14430, 14500, 16340, 17650, 21700, 26650, 32650. All of them have a standard voltage of 3.7 V, and the size of the element can be determined by marking: the first two digits correspond to its diameter, the second two to its length (both in millimetres). The larger the battery, the higher its capacity and, accordingly, the power supply.
Separately, it is worth noting that the 14500 cells are identical in size to conventional AAA finger batteries, but differ from them in operating voltage. In some flashlights this difference is taken into account, and they can use both types of power sources (with less battery life and/or brightness when running on batteries). However, in general, the possibility of such a replacement needs to be clarified in each case.
— Series CR****. Batteries — "coins" of a characteristic disk-shaped form based on lithium technology (not to be confused with lithium-ion batteries — in this case we are talking about disposable power supplies). The numbers in the marking indicate a specific size — for example, the CR2032 marking corresponds to 20 mm in diameter and 3.2 mm in thickness. Actually, CR2032 is one of the most popular sizes of such batteries; besides him, you can find CR1220, CR1616, CR2016 and CR2032 in flashlights. All such power sources are mainly used in compact low-power flashlights, in particular, key fobs (see "Type").
— Series AG**. The "AG" suffix with a number (one or two) is used to refer to miniature alkaline manganese type disposable batteries manufactured by Seiko and some other brands. The larger the number in the designation, the larger the size of the battery: the smallest of these elements, AG0, have a diameter of 5.8 mm and a thickness of just over 2 mm, and the largest (of those used in flashlights), AG13, are 11.6 mm in diameter and 5.4 mm thick. The main scope of such elements is miniature flashlights, including key chains.
— Series LR**. In fact, it is a complete analogue of the AG series described above **; the only difference is that AG is a brand name, while LR is used as a common international designation. In addition, there is no clear relationship in this standard between the number in the designation and the actual dimensions of the battery: for example, LR41 is larger than LR58, and LR44 is larger than both of them. Actually, in modern flashlights there are mainly just LR41 and LR44; they are analogues of AG3 and AG13, respectively, and have dimensions (length / diameter) of 7.9x3.6 mm in the first case and 11.6x5.4 mm in the second.
— 3R12. Batteries with a voltage of 4.5 V in a case of a characteristic shape: almost square and flat (70x60x22 mm), with rounded corners and two contact plates in the upper part. They were originally created as batteries for flashlights, but nowadays they are used quite rarely due to their large dimensions, shape features and relatively small capacity.
— PX28L. Compact and at the same time quite powerful cylindrical batteries with a nominal voltage of 6.2 V. They are well suited for working with a powerful load, including bright LEDs, but in general they are not widely used, and therefore they are rarely used in flashlights.
— R20. Another name for replaceable cells in size D is, more precisely, for disposable salt batteries produced in this size (other designations are used for other varieties). Usually, flashlights under R20 are compatible with any type D elements, however, the ability to work with salt batteries (having a lower capacity than alkaline counterparts, and even more so batteries) indicates a good energy efficiency and economy of the flashlight.
— CR2. Relatively small batteries (length — 26.7 mm, diameter — 15.1 mm), originally created for compact "soap" cameras — in the expectation that one such element could replace 2 AA batteries. The designation CR2 is commonly used for disposable batteries, batteries of this size are usually referred to as 15270.
— From the cigarette lighter. Power from the car on-board network through the cigarette lighter (or an auto socket of a similar format) can be found in two types of lamps. The first is hand lamps and auxiliary lighting (see "Type") designed for use with or near the vehicle. Most of these devices only work when connected to the cigarette lighter, and a fairly long (several metres) wire with an appropriate plug is responsible for the connection itself. The second option is miniature models (manual compact type and key rings) of “automotive” specialization. Such devices are equipped with their own batteries and are able to work autonomously, and the cigarette lighter is used to charge the battery — and the flashlight body itself plays the role of a plug (in other words, to charge, just insert the device into the cigarette lighter socket). However, both varieties are rare nowadays: in the case of lamps, the wire significantly limits mobility, and in the case of small flashlights, charging from the car network is not so often required. And even in the latter case, a more practical, versatile and convenient option may be a traditional rechargeable flashlight, supplemented by a car charger (see "Complete set").Water protection
This feature is indicated for flashlights whose housings have an increased degree
of dust and moisture protection. The degree of such protection may vary: for example, some models can easily withstand heavy rain, others “survive” being caught in a sea wave, and the most advanced ones can even be used when diving with scuba diving (see “Type -
For diving ”). The features of protection should be clarified in each case separately; however, if you need a flashlight that can withstand adverse conditions, you should definitely look for it among the models that explicitly state dust and moisture protection. Such models will be useful primarily for those who often have to work in difficult environments: climbers and other “extreme” tourists, rescuers, military personnel, sailors, etc.
The level of protection is indicated by two numbers according to the IP standard (
IP65,
IP66,
IP67...). The first number corresponds to dust protection (maximum 6). The second number indicates the degree of protection from water; here in protected models, level 7 (the ability to immerse under water to a depth of 1 m for half an hour) or 8 (the ability to work for long periods of time under water at a depth of more than 1 m) is usually found. Thus, the maximum degree of protection according to this standard is
IP68, completely sealed. There is also a marking like
IPX8, where the first digit is not indicated - this only means that the flashlight has not been officially certified for dust resistance. In the above example, this is not necessary - water resistance 8 automatically means a sealed case, impenetrable to dust.
It is worth considering that even completely sealed models may have different restrictions on the maximum immersion depth. So if you are going to intensively use the flashlight underwater, you should make sure that it can withstand diving to the planned depth.