Canon 7D Flash Sync

dTEA

dTEA

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I'm confused by the flash sync speed for the camera and flash gun.

As per title, I've got a 7D but also an old 500D too. I got a fully manual YN560 III and some 603 triggers. My presumption (as this is my first foray into flash) was that I could match flash speed with shutter speed. It looks like the menu only allows a simple 1/250 sync speed (1/200 on the 500D).

I wanted to be able to sync upto 1/2000 in part to separate subject from background etc.

Any ideas on how to achieve this with the current equipment; are there any settings? Any additional equipment if that's not possible?

As a quick test I have tried to mount the flash direct and force it via manual mode to shoot at 1/540, but that still seems slow?

Does anyone recommend a flash that can sync higher with the 7D and maybe I can use the YN560 as a slave/second?
 
The sync speed is limited by the time it takes for the shutter to expose the whole of the sensor at once.

The only way to get round this is to use high speed sync which strobes the flash to allow a higher sync speed.

Not sure if you can do this when the flash is not on top of the camera. And also think you may need a canon flash - not so sure about that though.

HTH

David
 
Not sure that does help! Although makes some sense. Anyone else got any workarounds? Other than using this as a secondary flash in slave mode I presume?

What speed can the canon based flashes achieve on and off the hotshoe? On a 7D. Or is the 7D not the issue?
 
You need to use something that supports the Canon HSS, so that the flashes fire many times in order to cover the whole of the shutter curtain sweep. I don't think the RF603 will do this, it will just tell the camera there is a flash mounted, but it can't talk to it, so you're limited at the cameras default shutter curtain limit of 1/250. Go beyond that and at some point you'll see when shooting against a white background only some of the background is exposed.

Grab a Yongnuo 3m OC-E3 cable, and a 430EX (or 550EX/580EX etc), or if you need longer, than you'll need to go ST-E2 or 580EX as the trigger flash.
 
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So , the camera itself is capable of higher speed...its solely the trigger for the flash sending a simple signal, and the flash trigger only being capable of one flash rather than a high speed burst that is causing the issue?

But if I'm right then j can use the YN560 as a slave triggered by the flash of the master?
 
dTEA said:
So , the camera itself is capable of higher speed...its solely the trigger for the flash sending a simple signal, and the flash trigger only being capable of one flash rather than a high speed burst that is causing the issue?

But if I'm right then j can use the YN560 as a slave triggered by the flash of the master?
Click to expand...
You're over simplifying the issue.
You need to put the slog in and read the articles. Or indeed the many posts in the lighting section here.
Canon and compatible flashes will give you HSS. Fully manual flashes won't. So your camera needs to think it's passing a HSS signal to a HSS enabled flash (the right triggers will convince it).

The right triggers (YN622 is the cheaper option) you can use higher shutter speeds and manual flash. But there are limitations, and you might need to be thinking about higher powered flash if you want to try that.

What are you trying to achieve? You might not actually need the higher SS, lots of people don't realise that the flash illumination time is effectively the shutter speed.
 
You're right. I'm trying to simplify as I've read quite a bit to begin with, but the shutter speed limitation was not part of it. I understood that the YNs were manual flash, and that the Canon ones offered TTL and auto expose the flash for the scene.

The possibility of separating the subject from the background was part of it. And still is. I suppose more reading to do, but experimentation is part of the learning. I appreciate all the input people...great to see so much knowledge on here. [emoji2]
 
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