All the time, I see new flash and strobe owners ask “How do I fire these things?, which isn’t an unreasonable question. For speedlights, it’s fairly straightforward. You buy the one that fits your camera’s hotshoe, slide it on, and beyond that you read the manual to figure out what all the different functions do. But what if you want to get it off your camera, or you’re using studio strobes?
In this video, Jay P Morgan shows us the three main ways to fire flashes with your camera. It’s fairly simple to do using either a sync cable, optical slave or radio slave. But each method has its own advantages and disadvantages. Not all methods suit all circumstances. So, it’s good to know and understand all three, and when might suit a certain situation best.
This is the “old school” way of doing things. A cable that plugs into your camera at one end, and then your strobe at the other. This method isn’t completely obsolete, though. Many strobes still often come packed with a sync cable in the box to get you up and running. They’re one of the most reliable methods you can use to fire your flashes, as there’s zero chance of interference.
The problem with sync cables, though, is that your flash distance is limited by the length of your sync cable. Yes, you can get really long sync cables, but they become more of a safety risk. The weight of long heavy cables can also potentially damage the sync socket on your camera over the long term. Unless you want to start picking up splitters with multiple cables, you’re also limited to only using one flash.
Optical Slave Mode
Optical slave mode basically solves the issue of only being able to trigger one flash with a sync cable. You hook your camera up to the sync cable with your main strobe, which is often the key light. Then you put your fill, rim, background and other lights in optical slave mode. When you take a shot, these lights see the key light go off, and instantly fire.
You don’t have to use this method with a strobe on a sync cable, though. You can also use a speedlight on your hotshoe in manual mode, or even the popup flash if your camera has one.
Optical slave mode tends to not work very well outdoors in bright conditions, though. Inside, in a studio, somebody’s living room or a similar environment, there are plenty of surfaces off which the light can bounce to fire the other strobes. Outdoors, though, the ambient light is very bright, and there’s nothing to bounce a speedlight off from your hotshoe for the optical slave units to see it firing.
The use of optical slaves is often hindered when strobes are behind or inside a modifier, too.
Wireless Radio Triggers
Wireless radio triggers are a relatively more recent invention. They have been around for a few years, but they’ve been fairly limited in design. A simple “dumb trigger” that tells your lights to fire using whatever settings are set on the flash itself whenever a signal is sent. Radio triggers are fantastic, because they offer you a lot more freedom.
Now, you’re no longer limited by the length of a sync cable. And you don’t have to worry about whether they’ll “see” another flash go off when your strobe’s inside a modifier or around a corner. And even the dumb manual triggers are fantastic. I still keep a whole bunch of Yongnuo RF-602 transmitters and receivers in my back for emergency backups.
In the last few years, though, radio triggers have come a long way. They now support high speed sync, TTL and full remote control with flashes 100 metres or further away from the photographer. This year, I switched over to using Godox strobes, which contain built in radio receivers for their own flash system. I am very much looking forward to replacing my trusty X1T transmitter with the new Godox XPro once it’s released.
There are many radio trigger options out there. Some are proprietary, solely for the use of one manufacturer’s lights (at least if you want remote control, HSS, etc). Others are more generic, or have a generic option for off-brand flash units. Some even have receivers that fully support off-brand flashes. Lots of potential options, so do your research.
The one thing I will suggest is to go with 2.4Ghz flash triggers. In many areas, 433Mhz triggers are notorious for picking up interference, firing randomly when you’re not shooting, and not firing when you want them to. I’ve had no such issues with 2.4Ghz in my regular shooting environments. Where even 2.4Ghz triggers can fall over, though, is in extremely busy wireless environments.
If you find that you’re suffering from radio interference, and flashes aren’t working as expected, that’s when it’s time to break out that sync cable or switch over to optical slave mode. Another big reason to still understand how to use optical slave and carry a sync cable is that your batteries may simply run out. Of course, the simple solution to that issue is to take spares.
As you can see, each method has its positive and negative points. As a general rule, I go wireless radio triggers with the Godox system. For backups I use the Yongnuo RF-602 manual triggers. As a backup to my backups, a couple of sync cables and optical slave mode.