Off-camera Speedlites with a Canon DSLR

So you are the proud owner of expensive Canon Speedlites but you don’t know how to set them up. I assume you have a Canon DSLR from 2012 or later and two Speedlite 600EX II-RT flashes. You need two light stands and an extension cable. Here is what to do.

Setting up bare flashes

What is the difference between a light stand and a camera tripod? They both have three legs, but a light stand is taller, does not support tilting and panning and includes a flange for attaching more kinds of lighting equipment. A cheaper light stand like the CowboyStudio Aluminum Adjustable Light Stand will also have a camera screw mount. For the moment I’ll assume you have one of these cheaper light stands.

Each flash goes on top of a light stand. You might wonder how you attach the “hot shoe mount” on the bottom of your flash to the camera screw mount on the light stand. The answer is easy. Included with your Speedlite is a carbon fibre foot. You might think that this foot is for setting the flash upright on a flat surface. And you would be correct. But it is also for attaching the flash to tripods (and low-end light stands). On the bottom of the foot is a threaded hole, which screws onto the light stand. Attach one flash to the light stand using the carbon fiber foot. This flash is the “slave.”

You only need one extension cable because just one flash (the “master”) is connected directly to the camera. The master flash and slave flash communicate with each other by radio signal. Canon does not make an official long extension cable but there are several aftermarket choices that work fine; search Amazon for “TTL cord.” You do not need to use the carbon fiber foot with the master flash, because the extension cable can mount directly to the light stand: the bottom of the extension cable has both a hot shoe mount and a threaded hole. Connect the master flash to the camera with the extension cable, then attach the master flash to the light stand.

Using flash modifiers

Bare flashes are often not the look you want: the lighting is harsh and makes your subjects look old. Most likely you will want to use a softbox, umbrella or some other kind of flash modifier. There are many YouTube videos and books which explain flash modifiers and flash placement.

A flash modifier does not screw to the light stand, and in fact better light stands such as C-stands won’t have a camera screw mount at all. Instead the flash modifiers attach to a flange on the light stand, and the flash attaches to the flash modifier. You won’t need the carbon fiber foot in this case. The cabling remains the same.


  1. Turn on both flashes. On the master flash press the “wireless/linked shooting” button which looks like a sideways lightning bolt. Choose the “master radio” option. On the slave flash press the “wireless/linked shooting” button and choose the “slave radio” option. The link light on both units should be green.
  2. Press the “mode” button and choose ETTL on both flashes.
  3. The four round buttons directly under the screen are called “function buttons.” If the label for “function button 4” does not say “Menu1,” press that button until it does. Now you are on menu 1.
  4. If both units say “A” next to “ETTL” on the screen skip this step. Otherwise, on each unit which says “M,” press “function button 1” (whose label says “Zm/C.Fn”) and turn the “select dial” to the left until the flash says “A” next to “ETTL” then press the “sel/set” button.
  5. On the master flash, press “function button 4” (whose label says “Menu1”) to get to menu 2. Then press “function button 2” (whose label says “ratio”) and choose “A:B.” Press “function button 3” (whose label says “Gr”) and turn the wheel to select your desired flash power ratio. (Try 2:1 and then adjust if it does not give the look you want.) Press the “sel/set” button to confirm your choice. Note: the master flash is always in group A.
  6. On the slave flash, press “function button 3” (whose label says “Gr”) and choose “B.” This means the slave is in group B.
  7. Position the flashes and you are ready to shoot.

Problems and solutions

The extension cable is a tripping hazard. Solution: You should secure the cable to eliminate the hazard. For more than occasional use, buy and use a wireless transmitter on your camera instead of an extension cable.

I set “wireless/linked shooting” but both units’ lights are not green. Solution: Make sure both are on the same channel.

The slave fired when I pushed the shutter, but the master did not. Solution: Master flash firing is set to off. On menu 2, press “function button 1” to turn it on.

I have more than two Speedlites. Solution: The same basic principles apply, though I would question whether Speedlites are the most economical option for what you are trying to do.

I am attempting to use Speedlites for UV photography but it is not working. Solution: Canon (and Nikon) flashes have built-in UV protection so you cannot use a Speedlite as lighting for UV photography. Use sunlight instead.