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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Stuart Carver's picture

Fstoppers community: don’t post about politics, we are a photography site.

Also fstoppers community: 28 comments and counting on a politics/human rights article, 0 comments on a photography related one.

Deleted Account's picture

Are you referring to the writers, the commentators or both?

Stuart Carver's picture

The people who comment mainly.. whining about all these politics/BLM/whatever else articles invading our photography space, yet only ever commenting and engaging with these articles, it would be funny if it wasn’t so sad.

Deleted Account's picture

I sometimes feel bad about the disparity in my own comments but find very little to say about the photography articles. After you weed out the beginner articles, which I don't read and those dealing with aspects of photography I don't care about, there's not much left. Among those, I find very little to say, aside from "I agree" or some other pleasantry.
When I was younger, I could never understand people watching golf on television, considering it to be the most boring waste of time imaginable. With the advent of photography sites, I now understand. They were bored...I'm bored.
As for commenting on politics/BLM/whatever, I'm human.

Matt Williams's picture

The translation is: "don't write about how things are changing, it upsets me because I'm not getting anything out of it or it inconveniences me slightly"

They could literally scroll right past, but nope.

Cool Cat's picture

Yes, transmitter & receiver is more logical. But people should grow up and stop being so offended with everything. I bet not one camera company ever conceived the idea that Master & Slave would be a terminology that would fit such a stupid narrative. It's hard to build something, but easy to destroy. The next time the younger generation burns down a building, does looting, or tears down a statue ask them what have they contributed to society. I bet the answer will be "nothing". Why not hide in your safe place like all the other cowards.

Simon Davies's picture

If their contribution to society is to shake racist morons like you out of your comfort zone, then I’d say that’s a pretty good one.

Btw you have entirely missed the point about master/slave.

Cool Cat's picture

Grow up and stop being so offended with everything.

Matt Williams's picture

lol you're offended about the very topic of this article. If it's "more logical" then why are you complaining?

BTW tearing down statues of racists *is* a contribution to society.

Cool Cat's picture

Might as well tear down the Pyramids in Egypt to your list and erase history while you're at it.

Jerome Shaw's picture

I always come to the comment section to see the echoes of "this doesn't affect me in any way so why change racist things I'm used to". Really gotta remember that some photographers are just as toxic as real life. Racist terms...too much PC, finally some diversity from companies?? another excuse comment to disregard the obvious. It's hilarious to see

Deleted Account's picture

Frequently, the things I find obvious are hidden to others. I'm never amused, much less find it hilarious.

Richard A. G. Lipscomb's picture

For photography how long has master and slave been used? Most photographers know these terms so I think many will have a hard time not calling a Speedlight on camera as a master to another Speedlight as the slave. Also, S mode is for the slave mode on many Speedlight.

g coll's picture

Fantastic! There is no reason not to do this.

Simon Davies's picture

But what have they changed them to?!

This is great news though. Small in itself but helps as a consciousness raiser. You can see from just the comments on this post that a lot of people still have a lot to learn.

That said, ‘transmitter’/‘receiver’ won’t work as replacements, because those are already used for flash trigger systems. Personally I like ‘parent’/‘child’.

Deleted Account's picture

By your logic, parent/child won't work for the same reason. After master/slave, I think transmitter/receiver is probably most well known.

David Love's picture

Removing, deleting, changing, tearing down anything someone considers offensive does nothing but erases the lesson behind why they are offensive. When we've erased history and removed any evidence that makes us look bad as a country, (Native Americans,antisemitism, slavery, treatment of women,) what do we have left to teach people why and how we did wrong. Seems more like out of sight out of mind and for people to learn, it needs to be in their minds.

But if we're going to remove words because they are racist, can we start with the N word in music and movies? My son has never heard that word and has no idea what the meaning behind it means or the history. He'll end up singing it while listening to hip hop music or hearing it in a film, keeping names and words that have no reason to exist around.

Deleted Account's picture

"Normal"? ;-)

Wheeler McGowan's picture

We all came from Adam and Eve. What is going on today is only serving to divide us further. False entitlement and hate will be the end of this society.

Deleted Account's picture

1. No we didn't.

2. No it won't.

3. Our shitty civilisation is terminal in any case.

4. LOL

Bruce G's picture

I understand and agree with Wheeler. My existence isn't terminal.

Deleted Account's picture

I would assume you may have finished seventh grade.


Bruce G's picture

Your assumptions...come from not knowing your destiny.

Deleted Account's picture

My assumptions "come from" your complete lack of English comprehension.

Go away, idiot.

Bruce G's picture

Ignorance is yours. You own it. (FYI... English was a minor) Go take another picture of yourself.

Deleted Account's picture

OK, what I said was ""our shitty civilisation is terminal"; you somehow interpreted that as "my existence isn't terminal".

I have no idea what the hell is wrong with you, and I do not care. But just a heads up, if you are going to claim educated expertise in English, you may wish to start writing in complete sentences.

Bruce G's picture

I took the time to read through many of your past comments. That is all I needed to understand you.

Deleted Account's picture

Oh princess, I'm afraid you are severely over-estimating your own abilities.

But by all means, produce your profile.

Bruce G's picture

I don't need a profile at my age. I came to this site to learn from those worthy of sound input. God bless you Walter.

Deleted Account's picture

You idiot. You said "I took the time to read through many of your past comments. That is all I need to understand you."

Fine, since you have developed a psychological profile of me, produce your profile.

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