Second Curtain On 5D With 580EX

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Help!

Just been trying to get my camera firing the flash 2nd curtain, and it ain't working... it refuses to fire at the end of the shutter length and fires immediately.

Canon 5D, custom function 15 set to 1, flash on hotshoe, ETTL... manual exposure, f/9 at 2 seconds... flash fires the second the shutter is pressed! :bang:

Why?

Do I need to set something up on the flash?
 
I want actual flash to be second curtain... no preflash was firing.

Unless... :thinking:

My batteries were in need of replacing... could it have been a pre-flash I saw and the batteries were too crap to charge to do the second curtain flash...? Hmmm... :thinking:
 
I want actual flash to be second curtain... no preflash was firing.

Unless... :thinking:

My batteries were in need of replacing... could it have been a pre-flash I saw and the batteries were too crap to charge to do the second curtain flash...? Hmmm... :thinking:

It's worth a try - eTTL needs a preflash to measure exposure so if your batteries were too low and the flash didn't recycle in time it might have missed the end of the shot.
 
I think that whatever mode the 580 is set for will override the camera, so unless that is set for second curtain, you'll still get first curtain. Give that a try.

BTW you cannot do second curtain remotely. Not that you were trying to do that, just saying. Unless the gun is on a hard-wire dedicated cord that is.
 
I think that whatever mode the 580 is set for will override the camera, so unless that is set for second curtain, you'll still get first curtain. Give that a try.

BTW you cannot do second curtain remotely. Not that you were trying to do that, just saying. Unless the gun is on a hard-wire dedicated cord that is.

can with simple radio triggers I tried it, set cam to second curtain and it fires the flashes at the end of the exposure :D
 
can with simple radio triggers I tried it, set cam to second curtain and it fires the flashes at the end of the exposure :D

No second-curtain remote sync with E-TTL that's for sure, but how did you configure things to make it work in manual with radio trggers?

Edit: I can't make it work with RF-602 triggers :thinking: I can see why it might (should) work except that I think Canon uses the E-TTL contracts for second-curtain triggering and these are only enabled when the flash is either on the camera or hard wired to it. New Pocket Wizard/Radio Poppers might do it though. Unless I'm doing something stoopid :D
 
THanks for the thoughts and comments so far guys... will get some fresh batteries today and see if I can find the manual too have a read too. :D
 
You need to set the flash to 2nd curtain, not the camera. Flash settings override camera setting. As for the radio thing, 2nd curtain should work with a radio trigger as long as your camera knows it's a trigger, not a flash. If you have a basic radio trigger you set the flash to manual, 1st curtain and set the camera to 2nd curtain - so the trigger gets activated at the end of the exposure and the flash then fires immediately.

The only way of having 2nd curtain ETTL of camera is going to be something like the new pocket wizards, but I'm not sure even that will work unless you change the setting on the flash.
 
You need to set the flash to 2nd curtain, not the camera. Flash settings override camera setting. As for the radio thing, 2nd curtain should work with a radio trigger as long as your camera knows it's a trigger, not a flash. If you have a basic radio trigger you set the flash to manual, 1st curtain and set the camera to 2nd curtain - so the trigger gets activated at the end of the exposure and the flash then fires immediately.

Cheers Andy, that makes sense - I'm going to have to try that for myself. :thumbs:
 
I just tried it with my 602s hoppy and nowt :S I'm sure I had it working with my PT-04s but I can't remember for the life of me how :S
 
68lbs, I had exactly the same problem with my 580EX and the 30D - just could not get it to fire at the end of an exposure... If you figure out what is wrong, please fill us in!

Cheers
 
Custom function 15 I'm sure 1 is first curtain and it's 2 that is second curtain (It's 1 by default)
 
I just tried it with my 602s hoppy and nowt :S I'm sure I had it working with my PT-04s but I can't remember for the life of me how :S

Yeah, me neither :( Every bone in my body says it should work, but it doesn't, I tried it with the transmitter in the hot-shoe and also connected to the x-sync socket. Nuffin. Fires on first curtain no matter what I set on the camera and 580EX. Tried it with a basic manual flash gun too. Nowt. Always fires on first curtain.

Only thing I didn't try was with the flash connected directly to the x-sync socket with a PC cord, as I haven't got one, but I don't think that would make any difference, because of the way Canon triggers second curtain sync.

Only thing I can think of is that Canon's second curtain sync command goes through the E-TTL contacts. This rings a bell. I believe Nikon is different in this respect and uses the main firing pin for everything, so it should/might work with Nikon. I also don't understand why Canon does it like this; I can't think of any advantage. It may be because of patent protection.

:shrug:
 
Custom function 15 I'm sure 1 is first curtain and it's 2 that is second curtain (It's 1 by default)

Done that bit Ali... 0 = first curtain, 1 = second :)

I'll try RicherSea's suggestion when I get home tonite... and arse, I've just remembered I forgot to get some bateries!
 
Ok, got it working on camera but not off. For anyone interested...

Camera is a Canon 5D Classic, flash is a Canon 580EX II.

1. ETTL Flash on camera - no need to set any custom functions anywhere, simply attach flash and press the high speed sync button twice til the 3 triangles shows (I always thought this was something for faster recycling to fire multiple shots... that'll teach me to RTFM!). You will get a flash at the beginning of the exposure to calculate flash power, then one at the end too.

2. Manual flash on camera - the same as above, except you decide the flash power so you don't get the pre-flash at the beginning of the exposure.

As I say.... I can't get it working off camera using Graham's 602 triggers. I am now wondering what the use of Cfn 15 is, as you don't need it for on camera, and it's not working off-camera. :shrug:
 
Ok, got it working on camera but not off. For anyone interested...

Camera is a Canon 5D Classic, flash is a Canon 580EX II.

1. ETTL Flash on camera - no need to set any custom functions anywhere, simply attach flash and press the high speed sync button twice til the 3 triangles shows (I always thought this was something for faster recycling to fire multiple shots... that'll teach me to RTFM!). You will get a flash at the beginning of the exposure to calculate flash power, then one at the end too.

2. Manual flash on camera - the same as above, except you decide the flash power so you don't get the pre-flash at the beginning of the exposure.

As I say.... I can't get it working off camera using Graham's 602 triggers. I am now wondering what the use of Cfn 15 is, as you don't need it for on camera, and it's not working off-camera. :shrug:

So, to engage second-curtain sync, you press the button marked second- curtain sync? That'll be the one illustrated on the opening pages of the manual for second-curtain sync, and described in the section headed Second-Curtain Sync :thinking: :lol:

I guess the custom function on the camera is nromally for an on-board flash, which obviously you don't have, but could be used for another Canon flash that doesn't have second-curtain sync function on the gun itself.
 
So, to engage second-curtain sync, you press the button marked second- curtain sync? That'll be the one illustrated on the opening pages of the manual for second-curtain sync, and described in the section headed Second-Curtain Sync :thinking: :lol:

:lol:

I guess the custom function on the camera is nromally for an on-board flash, which obviously you don't have, but could be used for another Canon flash that doesn't have second-curtain sync function on the gun itself.

That's what I do - didn't even realise that it was a function of the actual flash unit until I looked at a friend's Canon. My little Jessops fires on second-curtain using the camera settings.
 
That'll be the one illustrated on the opening pages of the manual

What's this 'manual' thing you refer to? All I got with my flash was a stand, a case, the flashgun itself and some booklet thing that I couldn't be arsed reading and tossed back in the box.
 
What's this 'manual' thing you refer to? All I got with my flash was a stand, a case, the flashgun itself and some booklet thing that I couldn't be arsed reading and tossed back in the box.

LOL I did the same when I got my flash gun/s ;) But in all seriousness, you need to read the manual to get the most out of any modern flash. They do a heck of a lot of different things and the way they work is, I find at least, not particularly intuitive. A lot of people don't even know that they use a pre-flash for all exposure calculation, which causes a lot of confusion and all sorts of sync problems when you try to hook up with studio flash.

This link may not be for you 68lbs, but it's a very good in-depth desciption of how Canon flash works :) http://photonotes.org/articles/eos-flash/
 
Just a quick question on this topic...

Does the pre flash fire before the shutter opens ? :shrug:

Mark
 
Just a quick question on this topic...

Does the pre flash fire before the shutter opens ? :shrug:

Mark

For eTTL it does - first flash is to allow the camera to meter the exposure, second flash is based on the power calculation and is the 'proper' flash.
 
So this is just for AV and TV ??

Would not pre flash if shooting in M

Thanks
 
Just a quick question on this topic...

Does the pre flash fire before the shutter opens ? :shrug:

Mark

Yes. It has to a) because this is what the camera's metering system uses for exposure calculation and its view is blocked the moment the mirror rises, and b) it must not be allowed to affect the actual exposure. You can see the pre-flash through the viewfinder.

What you cannot see through the viewfinder is the main flash of course. What confuses people is that the two flashes are so close together that they appear to the naked eye as one. But actually there are loads of flashes going on in the pre-flash, which is strobed at incredible speed like 40-50Khz.

First the exposure pre-flash goes off, at a known power. The camera measures it using the normal TTL metering system and makes instant exposure calculations, balancing flash with ambient if that's what you've set. With on-camera flash, the gun then fires at the required power.

If you are in remote E-TTL mode, after the exposure part of the pre-flash the gun goes into overdrive and puts out a stream of command pulses to tell the remote units what power to fire at, whether in HSS mode or not (it can't do second-surtain sync remotely) and it will instruct multiple guns to do different things. Only after that lot does it tell them to fire the main flash.

To see the pre- and main flashes separately, second curtain sync makes them visible at longer shutter speeds, or pressing the FEL * button fires the pre-flash so it is not repeated when the shutter release is pressed. Also, in full manual mode (not E-TTL manual) there is no pre-flash, just the main one.

This is all done with visible light, even though it is often called IR. The Canon ST-E2 master unit has a dark red filter over the flash tube, but it's not really infrared. All modern auto-TTL flash systems work in basically the same way. The red sensors on the front of the gun are not IR transmitters or anything. One is an LED focus assist light, and the other is just a sensor to receive the master flash's visible light commands.
 
So this is just for AV and TV ??

Would not pre flash if shooting in M

Thanks

The pre-flash is for E-TTL. It works in all camera modes, including Manual, Av, Tv, P etc.

You can also set manual flash power using E-TTL as a basic sync device. This still fires a pre-flash in master mode, to tell remote guns what power to fire at.

The pre-flash is fully disabled only in fully Manual, manual mode :D

I did say it gets complicated :lol:
 
It is complicated...

So in e-ttl mode on the flash, all camera modes use pre-flash.

The only time a pre flash doesnt occur is when the flash is set to manual
or the * FEL button is pressed before the shutter.

I get the classic people move after the first flash so their looking the wrong way..

So if i press FEL button first to do a pre flash exposure test, i wont get pre flash when i take a proper shot...


Thanks
 
Just had a quick try myself and after giving up rather quickly I found this,

http://luminous-landscape.com/forum/index.php?showtopic=36790

Canon need to find a soultion.

You would think that Canon could set their minds to this, and if it was easy I'm sure they would, but I'm guessing that their position ATM is that this is only a problem for a small number of people in pretty unusual shooting situations, for which there is a workaround fix that is not too difficult using optical remote triggers.

I'm thinking that the problem is that with second curtain sync, you want the flash exactly at the end of the exposure, and not approximately at the end. Different cameras with different shutter designs, perhaps with different amounts of wear, will require a different timing delay, even for the same nominal shutter speed, to get the flash timing just right.

I'm also thinking that the new E-TTL Radio Poppers should be able to do remote second curtain sync, because they use an optical/radio hybrid system which replicates the on-board flash exactly, ie anything that happens on- camera like E-TTL second curtain sync (which works on-camera) should work remotely. It's never that simple though!
 
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