The main purpose of this article is to acquaint those interested in the topic of lighting equipment with the technical solutions used by unscrupulous manufacturers from the Middle Kingdom to sell counterfeit products that copy famous brands. Here my subjective opinion will be stated, as a person who has come across firsthand with such equipment. In no case should this article be considered as a guide to action, so there will be no links to suppliers and sellers. Everyone has the Internet and if you want to use the search is not difficult.
The high cost of original solutions is obviously due to the manufacturer's desire to compensate for the labor costs for the development and production of highly specialized devices that are not aimed at a wide audience of users. This article will tell you how reasonable it is for a user who needs a fairly functional device, but who cannot afford it due to the high price, to look for an alternative in the form of a cheaper copy of the original device.
To begin with, I would like to tell you about the basic principles of the design of stage lighting complexes.
For those who know what DMX512, ArtNet sACN, etc. are. this part of the article can be omitted.
Basics
So, the basis of the entire light control system is the DMX512 protocol.
The DMX512 data transfer protocol was developed in 1986 as a means of controlling smart lighting devices from various control panels (console) through a single interface, allowing you to combine various control devices with all kinds of terminal devices (dimmers, spotlights, strobe lights, smoke machines, etc.). ) from different manufacturers. It is based on the industrial standard RS-485 interface, which is used for computer control of industrial controllers, robots and automated machines. For data transmission, a cable with two wires intertwined in a common shield is used.
The DMX512 standard allows you to control 512 channels simultaneously on one communication line (sometimes one device can use several dozen channels). Several DMX512-enabled devices working simultaneously allow you to create lighting patterns and design elements of the most varied complexity, both indoors and outdoors. One channel transmits one device parameter, for example, what color to color the beam, what pattern (gobo stencil) to choose, or what angle to turn the mirror horizontally at the moment, that is, where the beam will hit. Each fixture has a certain number of parameters that can be controlled and occupies a corresponding number of channels in the DMX512 space. Each parameter can take values ββfrom 0 to 255 (8 bits or 1 byte).
The following image shows a standard instrument connection diagram:
You can read more about the principles of the protocol in the article listed below in the sources.
The DMX512 protocol has a number of advantages and disadvantages, but it is now the main standard for most lighting systems.
Before the advent of a single digital protocol, control was carried out on separate wires with control voltage going to each device, or using a variety of digital and analog connections.
For example, the 0-10 volt analog interface was widely used, through which one cable was pulled to each device. The system was successfully used with a small number of devices, but with an increase in their number, it turned out to be too cumbersome and inconvenient, both in construction and in management and troubleshooting. This and other analog systems were unnecessarily complex, expensive, and lacking a single standard.
They required special adapters, as well as voltage amplifiers and inverters, in order to connect lighting devices from one manufacturer to the control panels of another.
Digital systems also did not differ in universality, they were incompatible with each other, and often used interfaces were hidden by developers. All of this was a clear problem for the users of such systems, as they were constrained in choosing one system to choose all the equipment from the same manufacturer, according to the same standard.
The disadvantages of the DMX512 protocol are:
- Weak noise immunity.
Operation of devices in conditions of strong radio wave interference caused by mobile communication terminals (i.e. mobile phones), nearby television centers, etc., electrical and lighting equipment: elevators, advertising signs, theater lights, fluorescent lights, or simply incorrect wiring DMX cable, may be accompanied by chaotic 'twitching' during normal fixture operation. This problem can be solved with the help of special devices (amplifiers, splitters, etc.). The disadvantage of this solution is the increased cost of installation due to the use of additional devices.
- Attenuation and re-reflection of the signal with a long line length.
The standard does not recommend connecting more than 32 fixtures to one DMX 512 line. If the line laid between fixtures is long enough or more than ten fixtures are connected in one chain, then there is a high probability that the fixtures will not behave correctly, and one of the main reasons may be own DMX signal pickup along the line. Simply put, the signal, having passed through all the devices, is βreflectedβ and the packets can walk along the DMX line back and forth. For such cases, a simple device called the DMX Terminator is used. The DMX line terminator consists of a ~120 ohm resistor.
- Low fault tolerance
Since the devices are connected in series using one line, damage to this line will make it impossible to control the devices that are located after the damaged section.
Devices that allow branching and improve fault tolerance help solve the problem.
Below is an image of a splitter that helps to branch the signal into several independent lines:
- Weak high voltage protection.
Many lighting devices use gas-discharge lamps, which provide a high-intensity luminous flux with a small size of the light source itself. To ensure the operation of such lamps, electronic circuits called drivers or ignition units are used (similar ones are used for xenon lamps in cars). These circuits operate at high voltage (several hundred volts). With a low quality of lighting devices, or their mechanical failure, electronic circuits may short circuit on the metal case of the device, as well as high voltage can enter the control line. In the latter case, the physical output on the control panel and even the USB interface may fail if the control panel is connected to a laptop or computer, which entails expensive repairs. All the same devices help to avoid this problem - splitters, which, as a rule, have opto-isolators in their circuit.
There are also wireless dmx signal transmitters. One transmitter can broadcast 512 channels, the same as one wire line. At the same time, in theory, an unlimited number of receivers can be programmed to receive a signal from one transmitter. Wireless devices transmit a signal at frequencies similar to Wi-Fi in the 2.4GHz band. They are at the initial stage of their development, because due to the small range and a large number of complaints about unstable operation (possibly due to the congestion of the 2.4 GHz radio channel), these devices have become widespread only in small installations used, for example, by DJs.
Art-Net protocol
The further development of the protocol was the integration of DMX512 into the Art-Net network protocol.
Art-Net is a simple implementation of the DMX512 protocol over UDP, in which channel control information is transmitted in IP packets, usually over a local area network (LAN), using Ethernet technology. ArtNet is a feedback protocol. As a rule, devices working on ArtNet have a function to respond to the received data. For example, the device has received data, and can send a response that it received them.
Artnet can transfer absolutely everything, even files. Initially, Artnet can transmit values ββand positions of faders, fixture coordinates, and can also transmit timecode (address-time code - digital time data recorded and transmitted along with an image or sound. It is used to synchronize various media systems - sound, video , light, etc.).
ArtNet devices use the so-called Nodes (nodes) for switching between them. The nodes can be Art-Net to physical DMX512 converters, or fixtures or equipment that already has a built-in Art-Net interface. Nodes can subscribe to (listen to) the server. At the same time, the server can distribute packets to all ArtNet nodes, as well as to selected ones. Nodes are somewhat reminiscent of a social network, they can be subscribed to the server at the same time, the server can ignore some nodes. A computer with lighting software or a lighting console can serve as an Art-Net server. The simplest way to implement the protocol is Broadcast, which works like a radio station. It broadcasts to all listeners, and listeners may or may not receive the signal.
Each space of 512 DMX channels in the Art-Net protocol is called a Universe. Each node (device) can support a maximum of 1024 DMX channels (2 Universe) on one IP address. Every 16 Universes are combined into a subnet (Subnet - not to be confused with the subnet mask). A group of 16 subnets (256 Universe) forms a network (Net). The maximum number of networks is 128. In total, the number of nodes in the Art-Net protocol can reach 32768 (256 Universe x 128 Net), each with 512 DMX channels.
Artnet addresses are usually used within 2.0.0.0/8, but in normal local networks 192.168.1.0/255 work without problems.
Advantages of Artnet:
- Possibility to carry out signal transmission over already existing LAN lines, as well as significantly increase the signal transmission range using inexpensive network equipment and sections up to 100m over unshielded twisted pair cable of the 5th category.
- A single Art-Net line can carry thousands of times more data than a physical DMX512 line.
- The Ethernet network has a star topology. This improves system reliability compared to the "ring" or "loop" wiring used with DMX512.
- Ability to use wireless network equipment such as Wi-Fi routers, access points, etc.
Among the shortcomings, the following can be noted:
- The maximum cable run distance is approximately 100 meters compared to 300m for the DMX512 system. However, given the lower cost of Ethernet switches compared to DMX512 splitters, this problem can be ignored.
- More cabling is required to implement an Ethernet star topology. However, due to the low cost of twisted pair, and since Ethernet can carry much more data than DMX512, the savings are still there. Also, ethernet star wiring will be more difficult when cabling around the farm. The best solution is to take the ethernet from the console to the farm and then convert to DMX512.
A visual diagram of connecting devices using nodes:
Most of the major lighting control software vendors support the Art-Net protocol, allowing the use of an Ethernet network instead of physical DMX512 lines.
Now let's go directly to the topic of the article - remote controls, consoles and interfaces for controlling lighting devices produced by the Chinese.
Let's get acquainted with the basic terminology:
- Interface - a device that does not have its own controls and allows you to output control signals from software running on a personal computer.
- The light console is either a stationary device capable of issuing control signals, or a controller connected to a computer or laptop and working in tandem with software. Faders, buttons, encoders, etc. act as controls, to which you can assign changing individual parameters of lighting devices, launching recorded scenes.
- A console is a device that essentially combines a PC with software and a controller with controls and signal output in one case. Typically has touch screen(s) and I/O ports found on most PC motherboards.
Sunlite and Daslight
I included these interfaces in the list, as I had a direct bearing on their distribution.
These interfaces do not apply to remotes or consoles, as they have limited functionality and a different logic for organizing the interface and controls.
The Daslight interface from Nicolaude in the maximum configuration allows you to use 3072 DMX channels. The output of 1536 channels is carried out through physical outputs on the interface itself. The other half can be output via the art-net interface.
Works on Windows and Mac. Currently in production, the latest official version is dated 13.01.2020/XNUMX/XNUMX
The Sunlite Suite 2 FC+ interface allows you to output 1536 channels via physical outputs and up to 60 Universe via art-net.
Works only on Windows. Currently officially discontinued and replaced by Sunlite Suite 3 interface. The latest version of Sunlite Suite 2 software was released in 2019.
Regarding prices, I will say that counterfeit is 7-8 times cheaper than the original. Given the high cost of the original interfaces, the copies are quite a bargain.
Of the minuses of copies, one can note: the inability to update the software (In the case of sunlite, this is no longer possible), to buy additional useful functions in the form of additional art-net universe, channels for standalone mode, etc.
The software is installed from the supplied disk, software downloaded from the official site will not work.
When you try to update the software, problems may arise in the form of errors in determining the interface by the computer, so it is better to limit access to the Internet for software in order to avoid problems. Of the dozens of interfaces sold, there were a couple of complaints from buyers trying to use the original software. Once I came across an interface with a factory defect, but was replaced by the seller without any problems.
T1 interface
Simulates the Avolites brand T2 interface. Outwardly similar to Sunlite Suite 2 and Daslight. The seller stated that the interface performs the same functions as the original T2, namely, it allows you to output two DMX streams and fully use midi commands and LTC timecode.
It also comes with Titan software on a flash drive, software version 11. It is possible to use up to 32 T1 interfaces at the same time.
Starting from version 12, you will need a special avokey key to use the software, so you should not expect updates from the Chinese in the near future.
The price is on average 3 times lower than the original.
Remotes and consoles Titan Mobile, Fader Wing, Quartz, Tiger Touch
Consoles are assembled in a rather artisanal way. The basis is an ordinary PC motherboard, to which various devices such as a controller, display, etc. are connected in a completely wild way.
It is not clear why the choice was made in the direction of conventional USB extension cables, vga cables, glued to the connectors with hot glue on both sides.
In the original consoles, everything is collected and fixed in a more civilized manner.
Reviews vary, for some these copies have been working stably for many years, for some the key has constantly flown. In general, how lucky.
If you buy it from reliable suppliers, according to the reviews of friends.
Prices differ by 3-5 times.
There are no complaints about the assembly of the Mobile and Fader Wing consoles, there is a drawback that cheaper components are used such as faders and encoders, so often their life is lower than the original.
Just like with T1, due to the use of the avokey key, updating the software to version 12 and above will not work.
Consoles and consoles Grand MA2
Consoles are represented by copies of MA2 Ultralite, Full, etc. models.
Here, in terms of assembly, a picture similar to titan is observed. The same usb extension cables and hot glue.
Interestingly, the Chinese produce unique devices that are not in the park of the original manufacturer.
These include the usb dmx expander interface, which connects to a computer via USB and allows you to use 4096 DMX parameters.
Several times requests for testing with the latest version of the original software were confirmed successfully. So far, there have been no complaints from at least a small number of buyers.
Another interesting thing is the Boss console.
There are various models that differ in functionality, appearance and characteristics of iron.
Despite the shortcomings, this device has an amazing ratio of mobility and functionality, which the original consoles cannot boast of. For example, it is possible to output 3072 + 512 parameters, incl. through physical outlets.
The assembly has already been mentioned earlier. With one particular instance, there were problems such as falling off the touch screen, etc. In general, stability leaves much to be desired.
Also on the market are counterfeit Command Wings, Fader Wings, and various Net Nodes. In terms of build and stability, like the titan consoles, things are better. There is experience of successful use of the Command Wing.
Cryptographic protection of devices and Grand MA software is still much lower than competitors, this allows the Chinese to produce copies of devices that fully work with official software.
As a result, I will express the idea that the use of copies in Russia is possible for those whose finances do not allow them to purchase original light control devices. As far as I know, the use of counterfeit products (sale is not meant here) is not regulated in our country, unlike in Europe or the West, where it can be equated with profiting from someone else's intellectual property and entail heavy fines.
Sources:
Source: habr.com