Flash sync leads are the Achilles heel of many a studio lighting set-up. Their problems are four-fold - they limit the distance between the camera and the nearest flash unit, they are easy to trip over, they can sometimes intrude into the picture area and they are prone to failing at just the wrong moment.
There are four possible solutions. The first is simply to be careful with sync leads and to ensure that you always have at least one spare. The second is to trigger the studio lights using a low power on-camera flashgun - fine provided that the flashgun used really does have a VERY low output but not so brief that the slave fails to respond. The third is to employ an infra-red trigger, which overcomes all the aforementioned problems. ButÉ infra-red sensors can sometimes be fired by flickering fluorescent lights, and any form of light can be hard to reflect round awkward corners or over long distances.
So the fourth triggering solution is to use a radio slave, which has a signal that is invisible, goes around corners (and through walls), reaches further than most applications demand and is unaffected by fluorescent lighting. On the down-side, radio triggers are expensive and illegal.
Yes, that's right: it is generally illegal to operate an unlicensed radio transmitter in the UK - and that's exactly what most radio triggers are. System Imaging's new set, which functions on a licence exempt frequency (418 MHz), is an exception. The device is based on remote-opening garage door technology and is claimed to have a range of 75-100m. Not surprisingly, the unit never failed to trigger during studio testing.
The set comprises a transmitter and receiver and costs £200 (extra receivers are also available). The transmitter is small and discrete. It has no on/off switch, being activated either from the test button or via the hot-shoe/PC cable contacts. When the cable is plugged in, the hot-shoe is disconnected, making it possible to slip the transmitter into an all-metal shoe purely for mounting purposes. Whether by careful design or lucky coincidence, the hot-shoe dimensions are such that the transmitter can be fitted onto a Mamiya RB67 without fouling the focusing knob (see picture).
The receiver is a little bigger and features an on/off switch. It also has a "power-on" indicator, low battery warning light and firing confirmation light, together with a sync socket and two channel selector. Mounting is less easy - the instructions suggest drilling a 4mm hole through the flash support bracket, but this is not a job that all users will want to do. A simple adjustable lanyard attached to the receiver, and long enough to embrace all monobloc housings, would be a less troublesome solution. The sync cable is terminated with a 1/4" plug that will fit most studio flash units. Adaptors for other types should be available by the time of publication.
To date, the Systems Imaging set has performed faultlessly. The £200 (GB pounds, approx $300 US) price tag is reasonable for what is being offered. An infra-red system may be about half the price but is also more limited in use. The beauty of slave triggers in general is that they can be used with different types of equipment, so need never become obsolete. For peace of mind, ease of use, versatility and value for money, the Systems Imaging radio slave set looks hard to beat.