550/580/ST-E2 Manual Mode

[gkas]

Wanting to have a little bit more control, I decided to try my 550 & 580 flashes in manual mode. I normally use them in ETTL mode with good results. I trigger them with the ST-E2.

After going over the manual again, I figured out that holding the Mode button down for 2 seconds allowed you to change the flashes to M mode when they're slave . Great. Good start. I set my 20D to 1/60 f/22. In slave mode 1/1 my 550 only gives me a reading of 1/60 f/1.0 on my Sekonic 558R when triggered by the 20D with the ST-E2. The ST-E2 always shows the ETTL light. If I manually fire the flash from either the ST-E2 or the flash itself, I get a reasonable reading like f/22. I tried turning off the preflash with the 550 CF 3-1 and using FEL to fire the preflash.

It seems like I'm getting a short pop when firing the shutter, but a full pop on test from either the ST-E2 or the 550. What am I missing.

[Lotto]

When you test the slave 550 with the 558R, did you push the test button? Because by default, the test button fires only 1/32 of the flash power.

[gkas]

When you test the slave 550 with the 558R, did you push the test button? Because by default, the test button fires only 1/32 of the flash power.

Are you sure on that? I get a louder pop when I push the test button, and the 558R reads closer to what I would expect, like f/22+ at about 4-5 feet. I think you get the low power pop when you have the flash set to ETTL. I have it set to M-1/1, so I would expect something close to full power.

[Lotto]

Opps, you are right about that when in slave or manual mode. I don't have a ST-E2, can you try to use the 580 as master on camera and do the same test?

[PacAce]

Wanting to have a little bit more control, I decided to try my 550 & 580 flashes in manual mode. I normally use them in ETTL mode with good results. I trigger them with the ST-E2.

After going over the manual again, I figured out that holding the Mode button down for 2 seconds allowed you to change the flashes to M mode when they're slave . Great. Good start. I set my 20D to 1/60 f/22. In slave mode 1/1 my 550 only gives me a reading of 1/60 f/1.0 on my Sekonic 558R when triggered by the 20D with the ST-E2. The ST-E2 always shows the ETTL light. If I manually fire the flash from either the ST-E2 or the flash itself, I get a reasonable reading like f/22. I tried turning off the preflash with the 550 CF 3-1 and using FEL to fire the preflash.

It seems like I'm getting a short pop when firing the shutter, but a full pop on test from either the ST-E2 or the 550. What am I missing.
When ETTL wireless remote is used, whether the flashes are in manual mode or not, there is always a preflash (which carries the wireless remote control signals) fired by the master just before the shutter opens. This must be what your L-558 is registering. I know if you were using the 580EX as the master, that's what it does. Since the ST-E2 does not fire any visible light (only IR), I'm assuming that the l-558 must also be sensitive to IR light and this is what's being measured. I know that it's not from the slave because in manual mode the slave does not fire a preflash.

[gkas]

Opps, you are right about that when in slave or manual mode. I don't have a ST-E2, can you try to use the 580 as master on camera and do the same test?

If I get time today, I'll try it.

[gkas]

When ETTL wireless remote is used, whether the flashes are in manual mode or not, there is always a preflash (which carries the wireless remote control signals) fired by the master just before the shutter opens. This must be what your L-558 is registering.

I seem to get a reasonably correct reading if I use test from the ST-E2. Wouldn't it send out the same control IR? The readings are only incorrect when I fire the camera shutter.

Time for a notepad and some experimentation....

[Kraig C]

There is an option to test fire with autoflash to use full or 1/32 power with the 580ex

c.fn-09
0=1/32
1=Full power

This applies to the pre-flash in ettl and ttl as well as the test fire button... In manual slave mode, the 580ex test fire button fires the strobe at the power output selected on the display.

[Kraig C]

I didn't find anything in the 20D manual about what power output is used for the FEL pre-flash. If you are using manual flash mode, I don't think it would be apropriate to use the camera's ettl FEL pre-flash button to trigger the slave flashes for metering purposes.

It would be a nice but it doesn't apear to be designed to trigger slave flashes for off camera manual flash metering.

[PacAce]

I seem to get a reasonably correct reading if I use test from the ST-E2. Wouldn't it send out the same control IR? The readings are only incorrect when I fire the camera shutter.

Time for a notepad and some experimentation....
In that case, the only thing I can think of is that when you use the test button on the ST-E2, the slave fires almost immediately upon seeing the command signal from the ST-E2 so that the light meter is able to register both the command signal and the slave test flash within the meter measuring window.

In the case of the camera shutter firing the flash, the master has to send out the signal before the shutter curtain opens. The slave then has to wait until after the curtain opens all the way before it can fire the flash. This interval might be longer than the measurement window of the flash meter. I'm just speculating here, though, since I don't know this for a fact but it seems logical enough to me though. :)

[Kraig C]

Since the 580ex is not connected to the camera, the camera does not know what mode the flash is set to, the st-e2 does not know what mode the 580ex is set to either. When using the FEL button on the camera, the st-e2 instructs the slaves to use their ettl pre flash for ETTL metering with the cameras internal light meter, since the camera has no power option for FEL pre-flash this will not work with an off camera flash meter because there's no option for slave trigering for off camera metering.

A custom functions option for full flash output with the FEL button would work nicely for what you are doing.

[Kraig C]

If you're gettin the same pre-flash meter reading from the 558R when you press the shutter as when using the camera's FEL what pacace mentioned makes sense.

The camera telling the st-e2 to pre-flash for ettl exposure metering, since the st-e2 is stuck on ettl all the time it makes sense that the 558R flash meter window is closed after the pre-flash.

Since there is no manual control over the camera's FEL output via custom functions, or manual override of the FEL signal into a "TEST" or "FULL" state with the st-e2 You will have to stick with using the test button on the st-e2.

[Kraig C]

The online documentation of the 558R flash meter mentions an accumulative, and non accumulative metering mode. Check those options, see what results you get, also try the meter with the flashes off to test if the st-e2 IR emmiter is triggering the flash meter.

[gkas]

Since the 580ex is not connected to the camera, the camera does not know what mode the flash is set to, the st-e2 does not know what mode the 580ex is set to either.

I only tried the FEL to see if there was any difference between the 550 CF3-1 which turned off preflash. I never tried measuring the flash when hitting the FEL, only the flash using that setting.

The more I think about it, I think the ST-E2 doesn't know that the 550 is in manual mode, since the ST-E2 ETTL light is ALWAYS lit when connected to the camera.

[gkas]

The online documentation of the 558R flash meter mentions an accumulative, and non accumulative metering mode. Check those options, see what results you get, also try the meter with the flashes off to test if the st-e2 IR emmiter is triggering the flash meter.

I tried both modes, and it never shows more than 1 flash, at the low reading, which I think is true.

Maybe I'll try taping the hotshoe contacts to turn off the ETTL.

[gkas]

Well, a few more comments to stir the mix. I tried taping the 2 (and 4) contacts on the flash shoe. It not only shut off the ETTL light on the ST-E2, but the 550 didn't fire, either.

I did verity that the manual mode was working, just not reading correctly on the 558R. I fired at 1/1, 1/2, and 1/4 and the histogram responded appropriately.

[PacAce]

I've lost track of what it is you're trying to do here. Were you just wondering why the flash meter was showing a very large aperture when you were using ETTL wireless remote with the flashes in manual mode and fired via the camera (I think I've already answered that in my previous post)? Or were you looking for a way to meter the individual flashes which you would like to trigger via ETTL wireless remote? If you wanted to meter them individually, then the best way to do that is to push the test button on each of the flash units. If you want to get an overall reading with all the flashes going off, then just hit the test button on the master and all the flashes will go off simultaneously and be reflected in the meter reading.

Now, this is how the above would work with a 580EX or a 550EX as the master. Since I don't have an ST-E2, I can't vouch that it'll work the same way, too. I dont' even know if the ST-E2 has a test button which you can use to fire all the slaves attached to it. If it does, then what I described above should work even with the ST-E2 as the master.

[Kraig C]

It does sound like the hand held meter is "closing the window" too soon. Try some more pin blocking on the st-e2, in different combinations, maybe you will find one that doesn't let the camera communicate the pre-flash but still lets the st-e2 work as a wireless transmitter. [edit for too much information] :P

[PacAce]

Wanting to have a little bit more control, I decided to try my 550 & 580 flashes in manual mode. I normally use them in ETTL mode with good results. I trigger them with the ST-E2.

After going over the manual again, I figured out that holding the Mode button down for 2 seconds allowed you to change the flashes to M mode when they're slave . Great. Good start. I set my 20D to 1/60 f/22. In slave mode 1/1 my 550 only gives me a reading of 1/60 f/1.0 on my Sekonic 558R when triggered by the 20D with the ST-E2. The ST-E2 always shows the ETTL light. If I manually fire the flash from either the ST-E2 or the flash itself, I get a reasonable reading like f/22. I tried turning off the preflash with the 550 CF 3-1 and using FEL to fire the preflash.

It seems like I'm getting a short pop when firing the shutter, but a full pop on test from either the ST-E2 or the 550. What am I missing.
Getting back to your original question, you are not missing anything except for the fact that you are using a light meter to read the output from flashes that are controlled via ETT wireless remoteL. There is nothing wrong with the ST-E2, the flashes or the camera. And you are not getting a short pop from the flashes when you fire the shutter. I think you are over-analyzing things here and making it more complicated than it really is. The only thing out of place here is the fact that you are using a fllash meter. Ignore the flash meter because whatever reading you're getting in this situation is totally bogus. :)

[gkas]

I was just trying to fire the flashes in manual mode, check the output with the 558R, then fire them with the ST-E2. I think the only way to meter is to fire each with it's own test button. The whole idea was to be able to use the meter to analyze the setup, and not have to fire a lot of shots and correct via the histogram.

I just tested, and all works correctly as long as you fire only with the test button. I set the M camera mode to match the 558R with each of the following, and they gave spot-on pics. Each was fired with noted test button, then set M camera mode to match. The pic was always taken on the 20D via the ST-E2.

550EX tested with it's test button, then test button on ST-E2.
580EX tested with it's test button, then test button on ST-E2.
550EX & 580EX 2 light setup via ST-E2.

Now that I know the ground rules, it's not a problem to fire via the test button.

All tested fine. It confirms that all tests must be fired via a test button, and not the camera.

Thanks for all the input. The answer seems so simple, but isn't that mostly the truth....

[PacAce]

I was just trying to fire the flashes in manual mode, check the output with the 558R, then fire them with the ST-E2. I think the only way to meter is to fire each with it's own test button.

I just tested, and all works correctly as long as you fire only with the test button. I set the M camera mode to match the 558R with each of the following, and they gave spot-on pics. Each was fired with noted test button, then set M camera mode to match. The pic was always taken on the 20D via the ST-E2.

550EX tested with it's test button, then test button on ST-E2.
580EX tested with it's test button, then test button on ST-E2.
550EX & 580EX via ST-E2.

All tested fine. It confirms that all test must be fired via a test button, and not the camera.
Yes, fire the flashes with the Test button on the individual flashes and all will be fine with the flash meter reading. Push the test buttom on the master and again all will be fine with flash meter reading.

Fire the flashes with the camera and try to measure the total flash ouput with the flash meter and you're not going to get the reading you thought you should be getting.

Glad you got that all squared away. :)