External lithium polymer battery for Canon: reliable power supply for autonomous photography expeditions.

Power bank in our time, this is a fairly common device. Many people use it to charge smartphones and tablets. At the same time, there are also such instances with which you can start a car in winter! Naturally, they can also be used as a source for charging the camera batteries.

When it comes to small outings, any PB will do. If photography is the main task of the hike, and the hike itself is quite long, 10-20 days, then the problem arises of providing photographic equipment with energy for all this time. The easiest option is to take the right amount of batteries. But on the one hand, this is quite expensive, and on the other, it is not clear what to do with these batteries later. PowerBank is a cheaper solution. Manufacturers offer PB with a fairly large capacity for little money. But so that there are no disappointments in the hike, it is better to take into account all their features, pros and cons.

• Power bank can be charged from different sources - usually it is USB, but there are options with power supply from 9-12V, respectively, such PB can be charged from the mains, computer, car cigarette lighter, solar panels and other things.


• Power bank has inside Li-ion batteries that do not work well in the cold. Those. in winter it is advisable to keep it warm.


• Power bank usually has a USB output. Moreover, there are options with two outputs, designed for different currents. There are also devices with additional 6-12V outputs.


• That is, first you need to figure out which chargers will be used and select PB with the required outputs.

Then everything seems to be simple, take a Power bank with the required capacity and charge whatever you want. But not everything is as simple as it seems.
In order not to be left without electricity later on the hike, you need to correctly assess its capacity, tk. what the manufacturer gives can be very different from what is actually there. Well, we must not forget that 20000mAh power bank and 2000mAh camera battery do not mean at all that one PB can replace 9-10 batteries.

How to estimate the real capacity of a Power bank

The actual capacity always differs from that declared by the manufacturer. They love pretty numbers with a bunch of zeros, but in reality, this is not always the case.
As a rule, standard 18650 cells are installed inside, as the most inexpensive and common. In this case, the manufacturer indicates the total capacity of the elements installed inside, often rounded up to a nice number.

For example, let's take a certain Power bank with a capacity of 16000mAh, which has dimensions of 60.4x145x22 mm. The size of a single 18650 cell is 65mm long and 18mm in diameter. Those. after some simple calculations, you can understand that in this bank no more than 6 such elements can enter.
Typical capacity of one cell is usually 2600mAh.

There are cells with a higher capacity, up to 3500mAh. But according to various tests on the Internet, rarely which one is capable of delivering more than 2400-2500mAh. They are able to give out a large capacity only when feeding low-power devices.

Those. we take a typical cell capacity of 2600mAh, multiply by 6 and get 15600 mAh. As you can see, given manufacturer only slightly rounded. But others can both throw more and honestly indicate the capacity. There are quite a lot of power banks on sale, the capacity of which is divisible by 2600, i.e. at least these manufacturers are not lying.

So, we figured out how to determine the capacity of a power bank.
Now we need to find out how much energy we really need.

If any device is powered, it is enough to find out how much energy it consumes and that's it, you can select a Power bank with the required volume and be happy. Losses in this case are small. It would be just wonderful if cameras could work from an external source.

Unfortunately, many cameras do not have this capability. Those. it is necessary to somehow charge the camera battery from the Power bank. And here is the main difficulty. During charging, several transformations occur and losses occur at each of them. The most efficient devices allow achieving efficiency up to 80-85%. But, unfortunately, in this case we are talking about homemade products of some craftsmen. It is difficult to find such devices on the mass market. And the real efficiency at best will be no more than 70%. Moreover, since the chargers are different, the exact value must be determined experimentally. The efficiency is rather low, because most chargers operate from relatively infinite sources and there is no need to optimize the circuits too much.

I tested two options at home and got an efficiency of 57% and 67%

In the first case, I used a Chinese charger powered by 12V. In the second, I charged it via USB in the camera (Sony mirrorless cameras now allow this).
As you can see, different devices have different efficiency and if there is a choice, then you need to choose a larger one, so as not to drag extra weight.

How to determine the efficiency of your charging system

First, we determine the power of the Power bank and the power of our battery.
18650 cells have a voltage of 3.7V, i.e. the power of one element is 2600x3.7 = 9620mWh or 9.62Wh.
I used four such elements as a source, i.e. their total power is 9.62x4 = 38.48Wh.

Power of one Sony NP-FW50 battery = 1080mAh x 7.4V = 7992mWh or 7.99Wh.

From four 18650 batteries in a Chinese charger, I managed to fully charge 2 Sonev batteries and the third to 75%. With the same four 18650 cells in the camera, it turned out to charge 3 batteries completely and the fourth by 25%.
Accordingly, in the first case, the total charged power turned out to be 2.75x7.99 = 21.97Wh, and in the second 3.25x7.99 = 25.97Wh
And finally, the efficiency in the first case turned out to be 21.97 / 38.48x100 = 57.09%, in the second - 67.49%

You can, of course, not do such tests, but take some value, the main thing is not to be optimistic and not count on an efficiency of 80-90%.

Knowing the efficiency of your charging complex, you can already quite accurately estimate what capacity of the Power bank we need. If you plan to charge other devices from PB, then their efficiency must be evaluated separately.

An example of calculating the required capacity based on the known efficiency

For example, I'm supposed to need to charge the NP-FW50 battery 5 times on a hike. The total required power gets 5x7.99 = 39.95Wh
Let's say I chose in-camera charging as the most efficient I have.
So, taking into account the efficiency of 67%, I need 39.95 / 0.67 = 59.63Wh or 6.2 18650 cells (59.63 / 9.62 = 6.2)

Those. I need to either look for a bank with eight elements (I have not met 7), or with replaceable elements, which I will need to take with me at least seven pieces. I chose a 2-piece swap bank. In this case, this is the layout:

	5xNP-FW50	7x18650 + Powerbank and wire
Weight, gram	267	398
Cost, rub	17450	4750

Those. having lost only 130 grams in weight, I saved almost 13 thousand rubles.
At the same time, I got the opportunity, if necessary, to charge any other device powered by USB. You also need to take into account that I can take any number of items, depending on the current needs - the gadgets used, the duration of the hike, etc.
Well, in terms of dimensions, here is a comparative photo (four 18650 cells, roughly equivalent to my three batteries):

In total, what you should pay attention to when choosing a Power bank:

1. The number of elements inside. Knowing the quantity, you can calculate the real capacity. Assess how much the manufacturer lied. Estimate the required amount of energy, etc.


2. The ability to replace elements. Power banks are on sale without installed elements. This makes it possible to independently choose high-quality elements or replace those that have failed. And most importantly, it allows you to take on a hike as many elements as you need, not being limited to the size of one bank or not buying a second bank if one is not enough.


3. Availability of 6-12V output. Car chargers can be used to different devices or power devices with the corresponding input.

And when preparing for a serious hike, you need to check everything again, because all Li-ion cells lose their capacity over time, regardless of use. Those. in a year or two, the capacity of the bank may decrease by a third, or even 50-70%, if the elements inside are of poor quality.

Likewise, the capacity and batteries of the camera lose their capacity. For example, my own battery sank by 25% in two years, another battery, non-native, but not the cheapest, sagged by the same 25% in a year. And I have already thrown out two cheap Chinese batteries, tk. they sank 75% over the year.

Those. when planning a serious hike, where it is important not to be left without power supply, it is necessary to check all available batteries and replace if necessary.

Li-Po battery pack in the field and disassembled into components: 1 - camera, 2 - dummy battery, 3 - T-connector, 4 - power wire, 5 - Li-Po battery, 6 - homemade battery case with belt clip.

Problem

There are situations when shooting on an expedition takes a long time and away from an electrical outlet. In this case, the capacity of the branded battery may not be enough for the entire trip. There are several ways to solve the power problem. Usually people buy one or two more batteries, but this is generally not cheap. It is risky to save and buy handicrafts from third-party manufacturers: as practice shows, their capacity, as well as the service life, may be significantly lower than that of a branded battery. The second problem is that when shooting at low temperatures and especially in severe frosts, even branded batteries lose their charge too quickly. Buying a battery pack, in which you can put 2 branded batteries, does not save the situation: all the same, the temperature of the batteries drops to air temperature.
In addition, batteries drain quickly with LiveView photography, movie recording, time lapse photography, and long exposures.

Solution

The logical solution is to make a large-capacity external power supply yourself. It can be placed under clothes in a warm place and supplied with high-capacity batteries. How to do it?
Fortunately, the manufacturer has provided everything you need for this. Firstly, all Canon SLR cameras have a special hole in the body for a wire to the ~ 220 V power supply, which is closed with a tight rubber plug. Second, cameras are designed to be used lithium ion batteries with a rated voltage of 7.4 V. They are electrically identical to high-capacity lithium-polymer (Li-Po) batteries (see the wiki) used by modellers. Of course their physical dimensions do not allow placing the battery in the camera, but this is not a problem - we will connect it to the camera with a wire! In the battery compartment of the camera, only two groups of contacts (+/-) are responsible for connecting the battery, and the power supply must be connected to them. To do this, you can either use the case of an existing battery (for example, a faulty one), or make a dummy of a branded battery with contact pads located in the right place.


Canon EOS 40D schematic with marked hole
for AC adapter cord

Safety engineering

Attention: Observe the rules of work with lithium-polymer batteries and be careful when charging them! Ignoring the safety instructions can lead to melting, explosion or fire of the Li-Po battery, and in the future - to fire!

Never charge a lithium polymer battery to an output voltage higher than 4.23 V per cell (cell) and do not discharge a Li-Po battery to a voltage below 2.7 V per cell!
If the voltage values ​​go beyond the specified limits, the battery will fail. In general, an external Li-Po battery cannot be charged with the charger supplied with the camera. To charge the battery, use only its balancing connector and only special chargers! Do not leave the rechargeable battery unattended!

However, with the right approach, lithium-polymer batteries are the most profitable in terms of price and in terms of the ratio of capacity / weight, capacity / dimensions and will last more than one year.

Assembly

Now to the point. For assembly you will need: a battery case or its dummy, a power wire with two copper stranded wires inside (2 meters), a 2-5 A fuse, a T-connector, a battery discharge indicator (aka "Li-Po buzzer"), heat shrink tubes with a diameter of 6 mm and 12 mm and, in fact, the battery itself.

1 - discharge signaling device, 2 - T-connector, 3 - fuse, 4 , 5 - the case of a defective battery, 6 - Li-Po battery, 7 - power wire

The power wire must be bought such that it has the lowest possible resistance. Each of the two wires in its composition should consist of a dozen thin copper wires and be covered with its own insulation. Do not use a wire in which each core consists of only one wire. This type of wire is designed for fixed wiring, it is laid once and for all, and when used in the field, it will just break very quickly.
Initially, I wanted to use a twisted wire as power, connecting the tube to telephone set, and as a result, the first version of the assembly did not work: due to the high resistance of the wire, the current in the circuit was very small, and the camera simply did not turn on, although the voltmeter showed the correct voltage value.
If you do not have a broken or damaged battery, it is not difficult to make a dummy out of wood (as in my version) or other non-conductive material. One option is sculpting plastic, on which you can place the contacts, make grooves for the wires, and then heat them up in an oven to harden.

The electrical diagram of the structure is extremely simple and is shown in the figure above. Lithium-polymer batteries, which are used by modellers, can deliver current, measured in tens of amperes for a long time. For this reason, you need to be especially careful with the contacts of the dummy and do not allow them to short circuit during the operation of the device. In order to prevent a fire in case of damage to the circuit, we installed a fuse right behind the battery. In general, its installation is optional and does not affect the functioning of the circuit.

The tools and materials that you will need are laid out in the photo. These are (1) tweezers, (2) a soldering iron, (3) soldering acid, (4) a utility knife, (5) a screwdriver, (6) heat shrink tubing, (7) a multimeter, (8) rosin, (9) tin-lead solder, (10) wire cutters and (11) round nose pliers.

The power wire is placed inside the old battery case, the wires are soldered to the new contacts. After assembling the power supply, the battery will just need to be glued.

Assembly. In general, everything is simple and clear. We solder the contacts of the dummy battery to the contacts on one end of the cable. As contacts, we used either tin strips 3 mm wide, or a rigid 1 mm wire laid in the grooves of the old battery case. For more reliable contact, 2 parallel conductors were placed in each groove.
Next, we put a small piece of 6 mm heat shrink tube on the wire, because then it will be impossible to put it on. At the free end of the wire, we remove the insulation for 6 cm and cut out a fragment of ≈3 cm from one wire. We solder the end of the fuse into this place, from the other end we solder a piece of wire so that in the end both ends of the power wire are of the same length. The soldered-in fuse wire can be covered with a thin heat shrink tubing. Then they need to be soldered to the short contacts of the T-connector, taking into account the polarity. Now it's time to move the heat shrink tubing from the middle of the wire to the soldering point and shrink it, then close the entire solder, including the T-connector, with a wide heat shrink tubing and carefully shrink it. We used an "air" soldering iron soldering station, but you can use the hot air from the lighter flame with caution.

Δ∇ Steps for assembling an external power supply for the camera

Ready! Now, having checked the polarity of the contacts of the assembly and the voltage, you can connect the structure to the camera. When shooting, the balancing connector should be connect discharge indicator("Li-Po buzzer"), which will warn the photographer about the impending discharge of any of the battery cells. This is necessary in order not to discharge the battery below the threshold of irreversible degradation. When connecting the discharge indicator, align the negative pole of the battery balancing connector (black wire) with the leftmost contact of the indicator. If you hear a sound and the indicator shows the battery status or voltage, then you can start using the assembly, but if nothing happens, try connecting the "buzzer" in reverse. Do not be afraid to spoil it, the device is protected against reverse polarity.

Ready assembly of the second version. In this more plausible specimen, we placed contacts on the body of an old faulty camera battery, used a battery with a larger capacity and installed a newer device with a beeper and a digital voltage indicator as a discharge indicator.

Advantages and disadvantages

. capacity is 3 times the capacity of a branded battery . the ability to shoot at low temperatures . the possibility of shooting at very long exposures . possibility of long video shooting . much more profitable than "native" batteries (5-6 times)

. the wire can be inconvenient when shooting . larger battery sizes ... the need to comply with technical safety when charging . lithium polymer batteries cannot be carried in the hold of the aircraft, only in carry-on baggage in the cabin

Resource calculation

According to the manufacturer's specification, genuine Canon batteries must be capable of shooting 800 (850) shots at + 20 ° C or 640 (750) shots at 0 ° C in the EOS 50D (EOS 5D MarkII). Considering the independence of the Li-Po battery charge from the ambient temperature (if it is under a jacket at body temperature), you can count on 3000 (2000) shots in all conditions using a 4250 mAh lithium polymer battery. Modern Li-Po batteries have a service life of about 500 charge / discharge cycles, which will make it possible to photograph for several years.

Solution price

Lithium polymer battery 7.4 V, 4250 mAh	1690 RUB	For comparison: one proprietary Canon BP-511A 1390 mAh battery will cost about 2400 ÷ 3500 rubles, two - already at least 4800 rubles. Canon batteries LP-E6 cost about the same.
Power wire, 2 m	RUB 48
Battery discharge indicator	349 r
Total:	RUB 2761

Calculation: November 2011, St. Petersburg. It is assumed that all the tools necessary for the assembly are already in place.

Stills from the last trip to Khibiny (10 days autonomously, the camera is powered by an external battery)

Note 1: my specific instance of the charger does not immediately turn off the power when the maximum voltage is reached, so I always monitor the voltage at the power connector with a voltmeter at the last stage of charging and manually disconnect the charger after it reaches 8.46 V.

Note 2: sounders on the "Li-Po squeak" were originally designed for use by modelers and therefore too loud, but they can be effectively muffled to an acceptable level by filling the holes with silicone sealant :)

Happy expeditions!

The author thanks Alexander Ryumin for the interest and excellent soldering of the assembly elements, Dmitry Grigoriev for the photographs of the power supply unit in the field provided to illustrate the article, and Alexander Ryumin at work; as well as all readers for their interest in the topic. Feel free to ask any possible questions in the comments.

Not always one regular battery digital camera enough for normal operation. For example, in time-lapse or other types of time-lapse photography, the battery may not be sufficient for the entire process. To increase the duration of continuous operation of the camera, special battery grips are used for 2 standard batteries or external power sources. Unfortunately, many cameras do not have "simple" interfaces for connection. external sources, and battery grips are not available for all cameras. But the problem of supplying power to the camera is nevertheless solved, and not by such complicated means. This article is about how to connect a universal power supply using a homemade dummy battery adapter.

Dummy adapter

In one of the previous articles (“From the practice of preparing for time-lapse shooting, or How the laws of“ falling sandwiches ”manifest themselves”) I wrote how to make a simple AA battery pack to power the Canon PowerShot G9 camera. This camera, like many others not designed for professionals, does not have a special connector for connecting an external power supply. Instead, such a unit is connected through a dummy of a regular battery, for which there is a special niche for a wire in the camera body. However, it is almost impossible to purchase such a sleeve adapter. I was lucky to buy an inexpensive analog of a regular battery and make an adapter out of it. But this is still luck.

It's good if the battery case is structurally simple and its dummy can be molded (at least from clay) or cut (at least from a piece of wood) with ordinary tools. But camera manufacturers are trying to make sure that third-party companies or craftsmen cannot start mass production of universal batteries and take some of the profits from them (in part, they, of course, protect us from potentially dangerous "left" products, but this is only in part). Body shapes and connectors change as regularly as camera models. Therefore, even when "upgrading" the camera of the same manufacturer, the photographer is often unable to use old batteries.

The most versatile Canon batteries in my stock are the old BP-511/512 - they were suitable for the first compacts and the first DSLRs. In modern lines, batteries from compacts and DSLRs of even the same generation, as a rule, are not interchangeable.

As you can see from the above photo, modern batteries have a rather complicated connector, which cannot be replaced with a pair of flat terminals. It is (almost) impossible to buy a "dummy" of such a battery to implement the idea of ​​powering the camera from an external power supply, and buying a battery to use only its body is too expensive (well, unless you are lucky to find a "substandard"). I will describe my own experience in making such a dummy, as well as using an external power supply unit "Vampirchik" (Mobile power supply "Vampirchik-Tsifra").

To make a dummy battery (LP-E8 type from Canon EOS 600D DSLR), slot-type terminals are required. A pair of terminals for the "+" and "-" pins were removed from the computer connector and mounted on the power wires.

You can find blanks for terminals for a dummy battery in computer and other connectors. The terminals for the dummy must first be tested on the contacts. As a test bench, we will use Charger"Simulated" battery. The terminals must hold well on the contacts, and the depth of the slot must be sufficient to securely grip the corresponding contact.

After the terminals are attached to the power wires (crimp and heat shrink tubing), proceed to making the battery case. The most in a simple way it seemed to me a process with molding or casting of a dummy blank from a hardening mass. Several blanks were made from different materials: epoxy based glue with filler, hot melt glue (for electric nail guns), clay based handicraft masses.

The first step is to create the form. If the dummy is made from a mass based on epoxy resin, then the form can be made from plasticine. We smear the regular battery with oil (I used an ordinary vegetable one) and form a plasticine form "around" it. We put everything together in the freezer. We are waiting (≈30 minutes) until the plasticine hardens well. Then we remove the battery without breaking the shape. If you attach a loop of thin stationery tape to the battery before molding, it will be easier to remove it from the mold.

At the second stage, plastic partitions should be installed in a well-cooled mold under the slots of the battery. And then put the appropriate terminals on them. The plastic partitions must be installed very accurately, otherwise the slots of the dummy will be in the wrong place and it simply will not fit in the chamber (or even worse - it will damage the contacts in the chamber!).

Form with installed baffles and terminals.

The third stage is filling the form. The LP-E8 battery requires approximately 30-40 ml of epoxy mixture. As a child, when I had to buy Soviet epoxy in large cans for all kinds of homemade products, I was upset that I couldn't buy smaller ones. Now in the store, as a rule, there are ≈10 ml packages and I regret that there are no big ones (and there is no perfection in the world). Consumption of the mixture can be reduced by adding a filler to the resin, for example, chopped rubber band. It is better to choose an epoxy glue that, after curing, will not be very hard (that is, if the description promises transparency and glass hardness, then this is not better, but worse). Then the dummy will not be pricked in the area of ​​the terminals, and the slotted terminals will be somehow "spring-loaded" by the elastic mass.

The process of filling a mold with a mixture of epoxy and cut gum.

The glue hardens quickly and after an hour or two you can remove the battery dummy workpiece from the mold. The more precisely the shape was made, the less additional processing with a file and emery cloth will be required.

Ready-made dummies of batteries for installation in Canon PowerShot G9 cameras (left, in the case of a regular battery) and EOS 600D (right). If you look closely, it is noticeable that one terminal of the homemade dummy is strongly twisted. During the solidification of the mass, it shifted from the correct position, and it had to be adjusted "in place" (it is better not to use such an adapter with the camera, so as not to damage its contacts).

With the described technology for making a dummy battery, I was not able to make a sufficiently good copy. No matter how I freeze the plasticine, the rigid wires still slightly turn out the terminal barriers, and the terminals after the epoxy hardens are not as they should be. Of course, you need to check this not on the camera, but on the charger. The terminal can be slightly bent, but this will not improve its mechanical properties, and the dummy in the area of ​​the terminals is destroyed. To get rid of this trouble, I broke the process of making a dummy into two stages: making a part with terminals and making the dummy itself. I used a charger as a slipway for the manufacture of the terminal part.

The area of ​​the charger, in which the terminal part will be formed, should be protected, for example, with office tape, and grease well. Then set the terminals in the desired position and make a formwork of thin plastic, into which the epoxy will be poured.

The terminals are installed in the charger.

Formwork in the terminal area, into which it is necessary to pour the epoxy mass.

Pouring epoxy into a charger is barbaric. But if you do everything carefully, grease everything well with grease (oil, silicone grease or silicone polish), which will prevent the epoxy from sticking to the plastic and contacts, then there will be no harm to the charger (you first need to experiment with the lubricants and the epoxy used). Pour epoxy through the groove into the formwork. We are waiting for it to grab well and remove the workpiece. In one case, when making a terminal part, I used poor lubricant (machine oil), and my structure stuck to the charger. Since this was the first experiment, I insured myself and did not wait for it to dry completely, but removed the "detail" while still wet. The remains of epoxy had to be removed with an awl and a screwdriver, but I did not damage the charger. In general, you need to take all possible precautions and first check the combinations "epoxy - grease - copper - plastic" for "non-sticking"!

Part of the dummy with clamps.

At the second stage of making the dummy, you need to make the mold again (from plasticine or in another way), install the terminal part into it and pour in the epoxy mass with filler.

An alternative method of creating a mold based on a standard battery cover (orange) and transparent packaging (from "blisters") plastic.

Ready adapter dummy.

As already mentioned, not only epoxy resin with a hardener and filler can be used as a material for creating a dummy. Any hardening mass or glue with slight drying shrinkage will do. I have tried a clay-based molding compound and hot melt glue. The advantages of these materials are that they stain less and do not smell, do not require special ventilation during operation. But they also have disadvantages. Clay crumbles at the point of contacts and wire exit, and hot hot glue cannot be poured into a plasticine mold - it will melt it. If you make a clay mold for hot glue, because of the high viscosity of the clay, it turns out to be inaccurate, and you have to bring the dummy to the desired size and shape for a long time (although it is quite simple to do this with a hot knife). In addition, with regard to hot melt glue, I am not sure that it will not soften in the chamber. The options for using clay and hot melt glue are presented rather in order to show their less usefulness in comparison with epoxy mass, and in case there is no epoxy in the nearest store, but there is clay, glue and a thirst for action.

Vampire-Number

About "Vampirchik" (drive / converter / power supply / indicator), I learned not so long ago from the article "Technology in the hands of a savage: 10 years later." Against the background, to put it mildly, of bastardism with branded batteries, it was simply impossible to believe in the existence of such a universal, useful and relatively inexpensive device. Nevertheless, the world turned out to be not so bad, and specialists and enthusiasts of real affairs have not died out in it yet. The device is amazing in all respects. It is both a storage device (2 built-in Li-Ion batteries 3.7 V 2200 mAh and a plug-in battery of an external battery pack), and a 4-15 V pulse converter with a current of up to 1.5 A (at voltages up to 5 V and with a proportional decrease when the output voltage rises), and an intelligent charging controller (from network adapter, USB, solar panels, bicycle dynamo) built-in batteries, and a controller for charging external batteries different types... In this case, the operations of charging the "Vampire" itself and power supply from it can be performed synchronously. There is a convenient LED indication and a built-in digital indicator.

Of the shortcomings, I can point out two: "urban performance" and the lack of tough protection from the fool. The first means that the "Vampirchik" is not designed for work in the rain or with strong shaking; it is better to keep it in an airtight and protected from mechanical damage case, and connect the devices to the connectors carefully. As for the "fool", it is more difficult with him - you need to come up with a defense yourself. So, I had the experience of shooting, when I used the "Vampirchik" to power the camera and after three hours of work I could no longer figure out how to insert the connector of the external battery pack (yes, its pin contacts are not protected by anything from an accidental short circuit to any small piece of iron - I just put on them a piece of clerical eraser-eraser) and stuck it into the "Vampirchik" the other way around. Well, this is "himself a fool", and there is nothing to be done. I think that if the protection "from the fool" was tougher, the device would lose its versatility.

A vampire with an external block of Li-Ion-accumulators (except for the block for 2 accumulators of type 18650, you can also purchase for 6). In total, in terms of capacity, such a set (3.7 V × 2.2 Ah × 4) is equivalent to four standard Canon EOS 600D SLR batteries (7.2 V × 1.12 Ah).

A vampire in a bag (one of the options with a belt bag) is connected to the camera through a homemade connector.

One of the functions of the "Vampire" is a digital indication of operating modes. It can be used not only to fine-tune the output voltage, control the charging of external batteries, but also, for example, to estimate the power consumption of the camera in various operating modes. Below is a table of the current consumption of the Canon EOS 600 D and PowerShot G9 cameras in different modes of operation. The values ​​of the current values ​​for short-term processes (half-pressing the release, release, focusing) are peak. If the value changes randomly, the range limits are shown. If the process is multi-stage (half-pressing - pressing the shutter - recording data - pause), several peak values ​​are given that can be attributed to different stages of the camera's operation.

Shooting mode / camera	Canon EOS 600D, EF 28-135mm IS, A	Canon PowerShot G9, A
/ display off	0,05	0,05
Camera on (shooting mode)/ display on	0,25—0,15	0,3—0,35
AF on / stabilization off / display off	0,3-0,5-0,05	0,25-0,35-0,1
Half / Release Press AF on / stabilization off / display on	0,3-0,5-0,15	0,35-0,3-0,3
Half / Release Press AF on / stabilization on / display off	0,3-0,5-0,05	0,35-0,3-0,1
Half / Release Press AF on / stabilization on / display on	0,3-0,5-0,15	0,4-0,3-0,3
Viewing photos	0,25—0,15	0,1
Watching a video	0,3—0,2	0,1—0,15
Flash charging	1,4—0,8	0,6
LiveView	0,6
Live View, Half / Shutter Press AF on / stabilization incl.	0,8-0,7-0,7

Most voracious consumers: flash and matrix with display in Live View mode. But on stabilization and focusing, as well as on viewing pictures (during brief views after shooting), it seems, you can not save.