Radio Trigger Guide
This article discusses radio triggers for flash and digital cameras. To be more precise, it is a survey of some of the most popular radio triggers that can be used to trigger an electronic flash or to trip the shutter of a digital camera from a remote location.
If you also are interested in optical triggers, please see this article.
1. Introduction
While optical triggers may be fine for wireless control of off-camera flash indoors, nothing beats radio for range and reliability outdoors. Also, if you want to have off-camera flash inside cars or behind furniture, radio is your best option.
Radio Frequencies
Several radio bands are made available for more or less unregulated use in different geographical areas this includes the bands used for RKE (Remote Keyless entry, i.e. garage openers) in North America, and the ISM (Industrial/Scientific/Medical) bands.
Equipment designed to operate in these bands is designed to be tolerant for interference by other equipment operating at the same frequency.
The common ISM and RKE bands available for industrial and commercial applications are:
- 220 MHz (ISM, China).
- 315-317 Mhz (RKE, North and South America, Japan).
- 340-354 Mhz (ISM, North and South America).
- 433-435 Mhz (ISM, Europe, Australia, Africa, China, India and some other countries).
- 869 MHz (ISM, Europe).
- 900-930 MHz (ISM, North America, and some other countries).
- 2.4 GHz (ISM, worldwide).
Note that because of the different frequency allocations, use of the 315-317, 340-354 Mhz and 900-930 MHz devices is illegal in Europe, and the use of the 433-435 Mhz and 869 MHz devices is illegal in the USA.
2. Low Cost Radio Triggers
In my opinion, TTL power control is great for a single on-camera flash, but when you start using several off-camera remote flash units, leaving control to the camera system does not always work well. I tend to use manual flash when I have several lights off-camera, so plain radio triggers is what I actually prefer to use.
These triggers are all produced in China and are sometimes referred to as Poverty Wizards or FleeBayTriggers.
Below, I plan to survey some the low cost alternatives that is available. Currently, I've only had time to test a single model: YongNuo RF-602. But I plan to add more as I can get access to units and can find the time for testing. Watch this space for updates.
YongNuo RF-602 (2.4 GHz worldwide)
The YongNuo RF-602 from YongNuoPhotoEquipment is probably one of the best cheap radio triggers currently available. It typically sells on eBay for USD 29 for a basic kit. (Search eBay for this item).
A basic kit consists of one transmitter, one receiver, batteries, and two cords: One cord with a 1/4" mono-plug for studio strobes, and one cord that can be used to trigger the shutter of a compatible camera (read about cord types below) by radio. There is also a 1/4" to 3.5 mm mono-plug adapter included in the basic kit.
It is unusual as far as plain triggers go, because it comes in two different versions, one for Nikon, Fuji and Kodak DSLRs, and another for Canon, Pentax and Samsung.
The main reason for this is that it is supposed to support the “wake up” functions of dedicated system flashes. A flash unit usually “goes to sleep” (standby) if it is left idle. The standby feature helps you save power and preserve batteries. You're supposed to be able to “wake up” a compatible flash in standby-mode with the RF-602 by half-pressing the test button on the transmitter.
The wake-up function does not work with all flash units.
- For the Nikon version, it is reported to work with all the legacy (pre i-TTL), while the Speedlight SB-800 is the only i-TTL compatible flash it works with. You can disable the standby function on any Nikon Speedlight, and this is what you need to do when you use the YongNuo RF-602 with the SB-600 and SB-900.
- It will not wake up the Sunpak PZ42X. To disable the sleep mode on the Sunpak PZ42X, hold down the mode and select (SEL) buttons as you power up.
The transmitter uses one CR2 3 volt Lithium Battery (included) The receiver uses two standard AAA 1.5V alkaline batteries (included).
The receiver should not be connected to a flash with a trigger voltage above 12 volts.
The transmitter RF-602TX has a metal hot-foot that matches the camera's hot-shoe. Underneath the transmitter there is four dip-switches for the 16-channel selector. There is a test/shutter release push button that has two steps, half-press and full-press. The battery door is is located at the back of the transmitter gives access to the CR2-battery. There is also a pc-socket of the screw-lock type. The transmitter has no on/off-switch.
The receiver RF-602RX has a metal hot-shoe. On the back of the receiver is there a proprietary port for connecting the included cables for camera and flash triggering. At the bottom of the receiver is a plastic foot which has standard 1/4" tripod mount and allows mounting the receiver on a flash stand or tripod. There is a sliding-type battery cover. The on/off-witch and four dip-switches for 16-channel selector are on the top of the receiver.
As noted above, the YongNuo RF-602 can also be used as radio-controlled a remote release for certain cameras. The image below shows some of the types of cord available.
The table below lists all available cords and what camera each cord is compatible with:
| Cord | Compatible camera |
|---|---|
| C1 | Canon DSLR: 550D 500D 450D 400D 350D1000D Canon Powershot: G10 G11 |
| C3 | Canon DSLR: 1D-series 5D-series 7D 50D 40D 30D 20D 10D |
| N1 | Nikon DSLR: D3-series D2-series D700 D300/D300s D200 Fujifilm: S3 S5 Nikon SLR: F6 F5 F100 F90/F90x/N90/N90x |
| N2 | Nikon DSLR: D80 D70/D70s |
| N3 | Nikon DSLR: D5000 D90 |
| S1 | Sony: a900 a700 a550 a500 a450 a350 a300 a200 a100. Konica-Minolta: 7D 5D DiMAGE: 9 7HL 7U 7 5 4X 3 |
| O1 | Olympus: E-400 E-410 E-420 E-450 E-510 E-520 E-620 E-30 E-P1 E-P2 E-PL1 SP-510 SP-550 SP-560 SP-565 SP-570 SP-590 |
| O2 | Olympus: E-1 E-3 E-10 E-20 E-300 E-100RS C2500L |
The YongNuo RF-602 operate in the 2.4 GHz band which is classified as an ISM-band worldwide (so you don't have to keep a separate set if you travel between Europe and the USA). If you are a Canon-user, it is nice to know that the 2.4 GHz band is not affected by 344 MHz radio noise emitted by certain Canon Speedlites.
The YongNuo RF-602 appears to be very reliable as long as you use good batteries. The best range is obtained by mounting the receiver with its long side facing the transmitter. In open space, this gives a maximum range about 120 meters.
YongNuo claims the maximum sync speed is 1/250 second. However, on a Nikon D700, the max sync speed appears to be 1/200 second. At 1/250, part of shutter obscures the frame.
I consider these units very good value for USD 29 for a pair. The fact that it can do double duty as radio controlled shutter release is a nice bonus.
3. Premium Radio Triggers
Professionals that want a solid construction, high reliability and extended range may pass on the low cost radio triggers described in the previous segment and instead go for one of the more expensive brands. These are described below.
PocketWizard MultiMAX (US: 344 Mhz, EU: 433 MHz, Jp: 315 MHz)
Photo: PocketWizard
When it comes to radio triggers, The PocketWizard MultiMAX is the gold standard. It is super reliable, but it will cost you USD 590 for a pair. And it will still not give you TTL. (Check prices at: Adorama, B&H, eBay.)
The MultiMAX unit has a dual function, where each unit can act as either as a transmitter or a receiver. You toggle between these two functions by flipping a switch.
The MultiMAX can be used both to trigger remote flash units and studio strobes, or to trip the shutter of a digital camera. There is a broad selection of cables available, making it possible to connect the MultiMAX to almost any type of flash, studio strobe or camera. To find the correct cable, please refer to the cable finder available on the PocketWizard web site.
The units are powered by two standard AA 1.5 volt batteries, with a typical life of approximately 60 hours. An optional AC adapter is also available.
One of the main features of the MultiMAX is up to 500 meter (1600 foot) triggering range. Several units can be relayed together if it is necessary to extend this range. It also has a close range setting to prevent the transmitter from jamming the receiver when working at extremely close range.
The MultiMAX lets the photographer select one of 32 digital channels, to avoid interference from other radio control units at crowded events where many photographers may be using such devices simultaneously. In addition, the MultiMAX lets the photographer set a unique identifier. This is an exclusive code installed on top of an existing channel. The receiver will only trigger if the signal it receives on that channel is signed with that code.
The MultiMAX has a clever zone control system with up to four zones (ABCD). Each zone can be switched on or off individually from the camera position. The receiver can be set to trigger on more than one zone. For example: If two photographers are working on the same venue, and agree to share area strobes that light the ceiling. In addition, each photographer has portable strobes that he move with him. One photographer could use zone A for his portable strobes while the other photographer could use zone B. The receiver triggering the area strobes could be set to zones A & B, and could then be triggered by both photographers.
The MultiMAX verifies each successful triggering and indicates misfires via audio and visual confirmation signals.
The MultiMAX also as a built in noise sniffer and signal strength indicator that can by used for finding the best channel and also for troubleshooting in environments with a lot of RF-noise.
Another unique feature is called SpeedCycler. This lets the photographer set up the MultiMAX for sequential triggering for up to four cameras or strobes. Applications include multi-angle camera shots, and and fast paced photo shoots. With four MultiMAX receivers connected to four cameras, the SpeedCycler will quadruple frames-per-second firing speed. It can also help to overcome recycle time limitations. By setting up four flash units connected to four MultiMAX receivers, the SpeedCycler will automatically trigger the next flash in line, while the three other flash units is recharging.
With Lag Time Equalizer Software, the photographer can measure the lag time between the camera trigger signal and shutter firing. This lag time can then be used to synchronise single or multiple cameras and strobes to fire in absolute unison with measurable accuracy to 1/10,000th of a second.
Additional features on the MultiMAX includes Rear Curtain Sync, Intervalometer, SpeedCycler and Multi-Pop (stroboscopic effect), contact closure adjustment, and trigger counter.
The unit has a USB-port and the firmware can be upgraded by the user with the help of a program called PocketWizard Utility
The versions for different geographical regions use different radio frequencies, and are not compatible with each other. Make sure you get the version that uses a frequency that is legal in the region you are going to use the unit.
PocketWizard Plus II (US: 344 Mhz, EU: 433 MHz, Jp: 315 MHz)
Photo: PocketWizard
The Plus II is a more basic model with the same 500 meter range and reliability as the MultiMAX, but without all the bells & whistles. It will will cost you around USD 340 for a pair. (Check prices at: Adorama, B&H, eBay.)
The Plus II is compatible with MultiMAX, and you can use one to trigger the other. It uses also the same cables, power supply, and other accessories.
The Plus II unit has a dual function, where each unit can act as either as a transmitter or a receiver. You toggle between these two functions by flipping a switch. It can be used both to trigger remote flash units and studio strobes, or to trip the shutter of a digital camera. There is a broad selection of cables available, making it possible to connect the Plus II to almost any type of flash, studio strobe or camera. To find the correct cable, please refer to the cable finder available on the PocketWizard web site.
The units are powered by two standard AA 1.5 volt batteries, with a typical life of approximately 60 hours. An optional AC adapter is also available.
The Plus II lets the photographer select one of 4 digital channels, to avoid interference from other radio control units.
The versions for different geographical regions use different radio frequencies, and are not compatible with each other. Make sure you get the version that uses a frequency that is legal in the region you are going to use the unit.
RadioPopper JrX (US: 916 Mhz)
The RadioPopper JrX system is a radio trigger that is not compatible with TTL. (Check prices at: eBay.)
You can trigger the JrX receivers with the transmitter from RadioPopper's TTL-compatible PX-system. Going the other way (using the JrX transmitter to trigger a hybrid PX receiver) is, according to RadioPopper, feasible with the Canon version, but does not work with Nikon.
The JrX comes in two flavours: The bare bones JrX Basic that costs USD 140 for a kit consisting of a transmitter and a receiver, and the slightly more sophisticated JrX Studio that costs USD 160 for a similar kit. Both kits use the same transmitter. The JrX Receiver Studio is capable of controlling the manual power control of selected flash units and studio strobes from camera position. Up to 3 groups can be independently controlled. To be more precise, the JrX Receiver Studio is capable of the following:
- The photographer can control the power of all current Alien Bees, White Lightning and Zeus brand studio strobes. Power levels are controlled directly from the camera position on with a JrX or a PX Transmitter.
- With the addition of a RadioPopper RPcube dedicated hot-shoe adapter, the photographer can control the power of past or present Canon and Nikon compatible flash units that supports analog quenching of the flash pulse directly from camera position with a JrX or a PX Transmitter.
Note that the RPcube is not compatible with flash units that does not support the analog legacy flash modes. The two units I know for sure it is not compatible with is Nikon SB-900 and Nissin Di866. It works fine with the Nikon SB-800.
The JrX Receiver Basic simply trigger when it receives the signal.
Both the transmitter and the receiver use one CR123a or RCR123a 3 volt lithium battery.
The cord connection used by RadioPopper is the same as PocketWizard connection. You can buy a PocketWizard cord compatible with your camera to use the JrX Receiver as remote shutter release.
So far, RadioPopper only makes a version of the JrX for the US 916 MHz band. There is no version that can be used in Europe.
4. Dedicated TTL Triggers
As far as I know, there only exists these two radio control systems that is compatible with the dedicated systems for wireless flash control that is part of the great Canon and Nikon camera systems. These are the RadioPopper PX and the PocketWizard ControlTL. Both are expensive.
I haven't had the chance to test either system, so the notes below are pretty sparse. Watch this space for updates.
RadioPopper PX (US: 916 Mhz, EU: 433 MHz)
RadioPopper PX was the first system available to offer the combination of TTL power control and radio, and it still the most popular system available today. It is available for both Nikon i-TTL and Canon E-TTL II. (Check prices at: eBay.)
PX is a hybrid system that takes the light signal that both Canon and Nikon use for flash wireless control and converts it into radio signals. This radio signal is then converted back into light at the receiver end.
Both the transmitter and the receiver use two AAA-size batteries. Both disposable alkaline and rechargeable NiMH will work.
The hybrid system makes use short fibre-optic cables to convert the
signal from light to radio and back again. To make it work, you put
your master dedicated flash in the hot-shoe, and attach a
RadioPopper PX transmitter to this with Velcro. You then
take a RadioPopper
Because the PX is a hybrid system, you actually need to have a dedicated flash that can provide the master flash signal. This is different from the other systems described on this page, where the transmitter goes in the hot-shoe instead of a master flash.
The PX-system supports Canon's HSS and Nikon's FP modes and is capable of syncing flash with the camera's shutter speed up to 1/8000th second.
RadioPopper do not say what range to expect, but users report that they work reliable up to at least 180 meters if there are no obstacles blocking the signal between the transmitter and receiver.
PocketWizard ControlTL (US: 344 Mhz, EU: 433 MHz)
Recently PocketWizard started to cell the PocketWizard ControlTL. So far, only a version for Canon E-TTL II is available. The version for Nikon is as of August 2010 still under development.
The ControlTL uses a transceiver called FlexTT5 that can be used both as a transmitter and receiver, or a cheaper transmitter called MiniTT1. Two FlexTT5 units cost about USD 410, while the cost of a MiniTT1 and a FlexTT5 is USD 390. (Check prices for the FlexTT5 at: Adorama, B&H, eBay.)
Unlike the RadioPopper PX system, this is a pure radio system where you place MiniTT1 transmitter or the FlexTT5 transceiver in the camera's hot-shoe, and then use a FlexTT5 transceiver with a dedicated hot-shoe to trigger the remote flash. The units are said to have a range of 240 meters for TTL, and 360 meters for plain triggering. The units are fully compatible with the MultiMAX and Plus II units for plain triggering.
The MiniTT1 uses a CR2450 3 volt lithium button battery, while the FlexTT5 use two AA-size 1.5 volt batteries.
Both units have a USB-port and the firmware can be upgraded by the user with a software program called PocketWizard Utility.
Both units features a dedicated hot shoe on the top. When you use the unit as a transmitter on the camera, it allows you to combine radio-controlled remote flash with on-camera flash. You may even use the on-camera flash for additional E-TTL II control by light. The unit automatically detects whether a dedicated E-TTL II flash or generic flash is mounted.
It supports Canon's HSS mode and is capable of syncing flash with the camera's shutter speed up to 1/8000th second.
Some newer Canon Speedlites, in particular 430EX, 580EX and 580EX II, are reported to have significantly reduced range with the ControlTL units. This is because these models emits strong RF noise across a broad spectrum of frequencies that interferes with the radio triggers. To resolve this, you can fit an external barrier that shields the RF noise, or modify the circuits inside the flash to filter the noise. See this note for details. Some Speedlites, for example the 550EX, 430EX II, 420EX, and 270EX do not have this problem.
The versions for different geographical regions use different radio frequencies, and are not compatible with each other. Make sure you get the version that uses a frequency that is legal in the region you are going to use the unit.
5. Final remarks
If you know about other radio triggers that belong in this survey, please use the comment field below to add your experiences.
6. Links
- User reports about various radio triggers:
-
Cactus PT-04 V2 wireless radio-based flash trigger, by N.K. Guy
Gadget Infinity PT-04 V2 Wireless Flash Trigger, by L7 Foto
YongNuo RF-602 Wireless Remote Review, by Dennis Dixon
- Radio trigger suppliers:
-
Alien Bees
Bowens Pulsar
Elinchrom EL-Skyport
Gadget Infinity
Hensel Studiotechnik
MicroSync
Pixel Enterprise Ltd.
PocketWizard
RadioPopper
Quantum
Secu-Line
YongNuo
Zap-Shot
