Canon Has Officially Dropped 'Master' and 'Slave' Terms

Canon Has Officially Dropped 'Master' and 'Slave' Terms

Since the global response for Black Lives Matter, many industries, including photography, have been shifting for the better. So, it's welcome news that Canon has officially dropped their master/slave terminology.

The terms "master" and "slave" used to be and in some cases still are commonplace in photography, especially when it comes to flash units. A master flash gun usually controls the trigger of another flash gun called the slave. This technique is used to synchronize multiple off-camera flash devices and is commonly used instead of wireless (or wired) triggers to either save time or money.

Godox XProN TTL wireless trigger

Flash guns set to master can be used to trigger other flash guns set to slave mode where wireless triggers, like this Godox XProN TTL, aren't used.

I spoke recently about my reservations with the master/slave terminology and some other issues I had with specific terms within the photographic community. I've since been in touch with Canon who confirmed, much to my surprise, that they've actually dropped the master and slave terms. In fact, they dropped them around the end of 2017. Here's what a Canon Europe Spokesperson had to say:

Canon started to phase these [terms] out since the end of 2017. [In] all new products and materials, these terms are no longer used. Products released before this time, and still available, will still have the term as it’s often a physical part of the LCD display so can’t be changed by firmware etc.

So, why then wasn't I aware of the terms being changed? I'm sure this is news to most of you as well. Well, they went on to say that the terminology change isn't yet immediately obvious to most customers because the terms are mostly used with flash guns, which are presumably less popular than the cameras and lenses. To compound this issue, the most popular flashes were launched pre-2018, so when customers use the manuals, the terms are still there.

Canon Speedlite 600EX II-RT flash gun

The popular Canon Speedlite 600EX II-RT speedlite was released in 2016, before Canon officially dropped the terms "master" and "slave."

Many photographers buy used gear, so will also not notice the terms change either on devices or in manuals for a little while, until the newer models start to drop in price and are more widespread in the secondhand community. But until then, at least it's good to know that Canon has dropped the terms. Who knows, maybe old manuals and flashguns will become more museum pieces, holding historic knowledge for the photographic community at large?

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133 Comments

Matt Williams's picture

Oh boy. Cue the outrage.

I always found 'commander' and 'receiver' to be better terms anyway.

Deleted Account's picture

I think "transponder" and "receiver" makes more sense.

Matt Williams's picture

Those are good too.

Deleted Account's picture

I'm sure you meant to write, "better" but it's all good! jk ;-)

Karim Hosein's picture

‘Transmitter’ or ‘transceiver’ would be more accurate terms. A transponder is a dummy device, which sends out a translation of an incoming signal. Indeed, ‘controller’, is a great term, as it does more than simply transmits what it is told to do, but is in charge of all the receivers, sending the appropriate signals to the appropriate strobes, and reporting the settings of each strobe.

Gary Pardy's picture

So true. Plenty of more informative, less antiquated (and insensitive) terminology that can be used.

Matt Williams's picture

Yeah, I mean master/slave isn't even as straightforward or as simple to understand, which does matter for various reasons, including photographers new to using flash.

Deleted Account's picture

Not that I'm defending the terms but, that doesn't make any sense. How is the term "camera" straightforward or simple to understand, if not by the fact everyone already knows it? "Master" and "Slave" are fine for the purpose, notwithstanding their unfortunate connotations.

Matt Williams's picture

He didn't say they were not understandable at all. He said they were more informative. And they are. Transponder/receiver can't be misunderstood unless you don't know what words mean.

Deleted Account's picture

I would argue, "transponder", but not "receiver", isn't a widely used/understood term. It is an interesting point but I hope the government would be disinclined to fund such a study. ;-)

Kirk Darling's picture

It's hard for me to imagine someone knowing the meaning of "transponder" and not knowing the meaning of "receiver" used in the same context.

Deleted Account's picture

Clearly, I was confused about "transponder" ;-) I meant "transmitter" but misstyped.

Gary Pardy's picture

Only for the fact that a "camera" is pretty narrowly defined - if I were to define it, a tool that senses light to produce an image or images, usually in the visible spectrum! "Master" vs "slave" is a relationship between two things - usually people! - and it's closest analogue is among the shittiest ways people have exploited one another.

Deleted Account's picture

I was referring to the word, camera, if one had never heard of such a device (silly, I know). Perhaps "Portable light recorder", although that doesn't exactly roll off the tongue.

If you're going to compare exploitive relationships, it's certainly shitty but I can think of worse. Of course, exploiting someone in a particular way doesn't negate the possibility of other, even worse, methods which I'm sure has occurred from time to time but have no idea of the frequency, not that it matters to those effected. What I mean is: in it's most benign form, slavery isn't significantly different from some employment situations you might encounter today but other, ancillary, elements are truly horrendous.

Jason Frels's picture

This master/slave nomenclature has been all over the digital world for decades and it has always bothered me. Newer interfaces use terms like 'controller / peripheral' or 'root / end-point', stuff that still makes sense without a human bondage metaphor.

The other thing that has always struck me as weird is the male/female genital metaphor for cables and connectors. That's the best we can do? I use pin and receptacle whenever I talk about it.

Gary Pardy's picture

I find that a bit odd too. I give it a bit more leeway for the fact that the male/female reproductive method is found throughout the animal kingdom (and other kingdoms!) and is not inherently rooted in exploitation. That said, there are better terms out there that don't immediately reinforce the male/female relationship as being based primarily around insertion!

Matt Williams's picture

The only defense of male/female I have is that it is applicable to so many more things than just cables or electronics, beyond which pin/receptacle wouldn't make any sense. I think it's the only term that could apply to all of those different things, from a cable to a pipe fitting.

Plus, those terms are not offensive in the way master/slave is, and as Gary says, male/female is not exclusive to humans.

Mostly though, it's point #1 - I can't think of other terms that would be so universal.

Burt Johnson's picture

This is beyond silly. The terms were very descriptive of the relationship between the two, and a heck of lot more obvious to the newbie than 'transponder'/'receiver'.

This is taking Political Correctness way beyond anything a rational person would consider appropriate.

Spy Black's picture

You don't mind if your boss calls you slave then, right?...

Deleted Account's picture

Compared to "receiver"? Hmm...

Alex Reiff's picture

To be fair, if your employer does a lot of shipping volume or is an NFL team, that might already be your job title.

Lee Christiansen's picture

Context is everything, but it does require thinking - something that seems to defeat conversations sometimes...

If Slave and Master are in context of people, then this is an issue.

If it is in context of a camera and a speedlight, then there is no issue.

There is a bigger world out there, with more than one meaning to a phrase or a word. If we start to shy away from simple words because they are offensive in other contexts, then we're going too have some real problems with almost everything.

Next we'll have chess sets that can't have black and white pieces, and certainly complaints of how the white player always starts the game. We can link almost anything to almost anything if we try hard enough, and to do that just waters down the valid arguments and problems faced by inequality.

If we start doing all that, then half the programmes we watch will be banned, because somewhere along the line we can find something that could possibly suggest something - if we extrapolate hard enough and associate enough things with other things.

Context is everything.

Kirk Darling's picture

As one comedian has recently said about cancel culture, "Everyone is an asshole if you study them closely enough."

Ruud van der Nat's picture

Speedlites are not people, they don’t have rights or feelings that can be hurt. And how are we going to call master and slave cylinders in hydraulics. How are we going to call the people in Eastern Europe instead of the Slavish people.?
Slavery is a very bad thing, and it still exists, we should concentrate on that. Racism also a very serious subject and seems to be increasing and should be combated. Renaming strobe units doesn’t help imho.

Spy Black's picture

Seriously tho, I've never actually called them master and slave, simply transmitter and receiver.

Matt Williams's picture

How is slave/master more obvious to a newbie than "transponder" (which is quite clear as to what it does) and "receiver" (again, extremely damn clear).

When I first learned flash I'd read about slaves or using a flash to trigger slaves and I was confused as hell.

Deleted Account's picture

When I first learned about flash, the terminology was the least of my confusion! ;-)

Gary Pardy's picture

That's legit funny

Matt Williams's picture

ok this is very true hahaha

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