Question to 7D users (Built in Speedlite Transmitter)

Hi guys!


I plan to buy a 7D, in Summer...

I have some questions tough:
How exactly does the built in Speedlite Transmitter work?!

- Must the built in flash be used to get it work?
- Can it fire also older flashes (420EX, 550EX)
- Must it have "eye contact" with the flash, or is it with some kind of radio transmission?
- Can it fire, for example Studio Flashes?
- How big is the reach of the transmitter?
- Can multiple 7D-s with Flashes be used simultaneously by different people (so that i don't fire off the flash, of the other guys)?
- If I buy a 7D, makes it any sense to buy a Canon ST-E3-RT?
http://the-digital-picture.com …tter-ST-E3-RT-Review.aspx


Thanks guys.

Here is a little FAQ on this topic.

https://photography-on-the.net/forum/showthre​ad.php?t=767760

Yes.

Yes

The 7D's control system is optical; the slaves need to see the 7D's flashes. No radio involved.

If they have optical triggers, yes if meeting certain criteria.

Depends on how well the slaves can see the control flashes. Canon claims about 20 feet outdoors and 30 feet indoors.

Yes. The system has four channels.

Only if you buy one or more 600EX-RT's.

Thank you Vorlon1 and Oldvultureface, exactly the answers I was hoping for.

(Well in fact, I was hoping it is Radio Transmitted)


You guys helped me a lot there, thank you!

If used for anything but occasional use, indoors, close up, I found the flash commander to be less than a desirable wireless option. In fact it down right sucked.

And has anyone have had experience with the Canon ST-E3-RT?
http://the-digital-picture.com/Revie...RT​-Review.aspx

The two options I'd be looking at:

1)Get an EXII speedlight or Yongnuo clone, along with a set of YN622c's. This gives you full flash control from the 7D menuing.

2)Get an ETTL trigger (if you feel you need ETTL) and use what you have.

The new Canon speedlights and ST-E3's are nice, but do you want to spend the money?

windpig wrote in post #15567023
The two options I'd be looking at:

1)Get an EXII speedlight or Yongnuo clone, along with a set of YN622c's. This gives you full flash control from the 7D menuing.

2)Get an ETTL trigger (if you feel you need ETTL) and use what you have.

The new Canon speedlights and ST-E3's are nice, but do you want to spend the money?

Well, I now have one 580 EX II, and two 430 EX II, and to be honest, it most of the time is a pain in the .... to use them together...

That is why I am looking forward to buy some 600EX-RTs

Okay, its a plan for Summer, but nevertheless, its the plan

I used one of those plastic bouncers on my pop-up so my trigger flash was indirect. It was able to set of a pair of YN565ex behind umbrellas.

NemethR wrote in post #15567041
Well, I now have one 580 EX II, and two 430 EX II, and to be honest, it most of the time is a pain in the .... to use them together...

That is why I am looking forward to buy some 600EX-RTs

Okay, its a plan for Summer, but nevertheless, its the plan

Ya, you get past one and it turns into a cluster f**k. It really requires an evaluation of whether speedlights provide enough power for your shooting to justify spend that kind of money. If so, the 600's and ST3 would be the way to go.

Don't really have other options then Speedlites in the dark, shooting Motorsport.

If you need ETTL, then I would say so.

Good answers above. But there are some other things you might need to know...

The built-in wireless flash uses white light to communicate with the flashes... firing the built-in flash with a bright stroboscopic effect. It's fairly obnoxious. The ST-E2/E3 use a near infrared light that's a whole lot less obnoxious. This is also true if using them for Focus Assist, the built-in flash strobes white light while the ST-E2 emits a reddish colored grid that's a lot less intrusive. The ST-E3-RT cannot do Focus Assist... You'll need the older ST-E2 or one of your Speedlites to do that.

Also, firing fairly rapidly and continuously, the built-in flash can overheat and shut itself down. The ST-Ex won't overheat. The shutdown is a temporary precaution to protect the flash and the camera will resume flashing after the flash has cooled down.

You don't need the ST-E3-RT to control 580EX and 430EX, since those flashes cannot be radio triggered with it. I'd suggest you buy a used ST-E2 or pick up one of the clones (Yuonguo on eBay, $99 US new). You can get these for 1/3 or less the cost of the ST-E3-RT. The clones claim to have more reach than the Canon, but I have heard they can overheat and shut down temporarily with extensive, continuous use.

Later if you acquire 600EX-RT Speedlites, you may want to upgrade to the ST-E3-RT at the same time.

The biggest problem I've always had using the ST-E2 and older flashes off-camera, is the line-of-sight limitation. With the ST module in the camera's hot shoe, it's hard to position the flashes where they won't be within the image. However, using an off-camera shoe cord and putting the ST module on a flash bracket that can be rotated (instead of in the hot shoe), it might be possible to set up the flashes behind and/or above you or off to one side or the other. The ST module beam is limited to something like a 60 degree arc, if memory serves.

There are radio triggers that can be bought relatively inexpensive, that can be used with all the ETTL flashes and most Canon bodies capable of firing ETTL. The Yuongnuo YN-622 and YN-622C sell for around $90 US for a pair and there seem to be a lot of fans. I am not sure if they can be used to trigger studio strobes (I imagine so, tho of course the strobes will be purely manual, won't be ETTL or ATTL controlled).

You will likely see some limitations that might effect shooting motorsports. For one, flash recycling decides how rapidly you can shoot. I use rechargeable AAs and a Compact Battery Pack to help 580EX II recycle as quickly as possible... but it's nowhere near the frame rate of the camera. If using the flash as fill and not too strongly, often you can get two or three frames before the flash has to shut down and recycle. If firing it as full flash, it can need to recycle after every pop (same will be true with studio strobes, they vary in their recycling rate depending upon model).

Is 1/250 top sync speed fast enough for motorsports? I'm asking because with any Speedlite you will have two alternatives: One is to set High Speed Sync, which will allow you to use higher shutter speeds but will seriously limit the flash's reach. The other is to set Rear Curtain Sync, preferable with moving subjects (especially with fill flash, when some of the ambient light is being recorded, too). However, you cannot use both these features at the same time. You have to choose one or the other.

IMPORTANT EDIT: I just learned that 600EX-RT fired with ST-E3-RT cannot do rear curtan sync! This might be a major fail for motorsports photography, if you think you'll want this feature a lot. I am stunned to learn this... I guess I'll be sticking with my older flashes (550EX and 580EX) and perhaps strapping them to some radio transmitters instead.

Not saying it can't be done... Just that there are some things to think about.

NemethR wrote in post #15564909
Hi guys!

Hello!

It's a nice camera, I have one.

No worries!

It's pretty simple.

The pop up flash sends a series of light pulses which has a bunch of information encoded into them. The slave flashes have a little sensor on the front of them that can see these pulses and decode the information. This information tells them when to fire and how strongly to fire.

Yes. The 7D uses the pop up flash to send the encoded light pulses.

If the slave flashes can work as a wireless slave using Canon's wireless system, they will work.

The slave has to be able to see the light pulses from the pop up flash. This doesn't always mean a direct line of sight though. You can bounce the light around corners, for example.

Not really. As I said earlier, it's designed to work with Canon's wireless flash set up. Unless the studio lights can understand the light pulse code Canon uses, they won't fire.

A way around this is to set the pop up flash to manual and attach a basic optical slave to the studio light. This way the studio light just fires when it sees the pop up flash go off. However, you lose a lot of the functionality by doing this. For example, you lose the ability to use automatic flash, and you have to adjust the slave flash's output from the slave itself.

it depends on the conditions.

On a sunny day it won't be too far. A few meters at best. On a dark night it will be further. I've managed to get mine to trigger from about 20 meters away, but that was at night, and it was using a 580EX as the master instead of the pop up flash.

Yes.

Canon's wireless flash system has different channels. You can be shooting alongside another photographer, and if you are using Channel 1 and he is using Channel 2, then you won't set off each others flashes.

- If I buy a 7D, makes it any sense to buy a Canon ST-E3-RT?
http://the-digital-picture.com …tter-ST-E3-RT-Review.aspx

it depends. If you are going to be using the 600EX-RT flashes as your slaves, then you can use the ST-E3-RT as a radio trigger. This has some pretty significant advantages, as you do not need to make sure your slaves can see the master, and you can put your slaves much further away.

But the 600EX-RT is the only flash that will be triggered by the ST-E3-RT master unit. If you are using other flash units as your slave, the ST-E3 won't work. It's radio only.

There is the ST-E2 master unit, which works on the light pulse system, but you do lose some functionality with that. You don't get manual flash, and you can only control groups A and B. No group C. Using your 7D's pop up flash, you get both group C and manual flash.

Thanks guys.

No worries!

Check out this link for my complete tutorial on how to use Canon's wireless flash system.

Wow, thank for all that info Amfoto1.

I use the canon CP-E4 to charge my 580EX II, when needed.
Okay, I am not shooting that much in the dark, but better have to shoot with something, then be unable to shoot.