Triggering flashes

[riyazi]

I was reading up about triggering flashes on this post (http://photography-on-the.net/forum/showthread.php?t=528785)and I have a few queries

1) if I trigger flashes using PW, Skyports or the Cactus triggers then I would need to set the flashes on manual mode and that ETTL would not work ?

2) If I use an ST-E2, the information sent to off camera flash is based on ETTL? From what I understand of ETTL, this is not possible as the camera would not have any information about where the off-camera flash is placed. So, effectively if using off-camera flashes, ETTL does not work - is that right ?

3) What would be the difference / advantages of using cactus triggers as opposed to cheap optical slave flash triggers ($5-$6 on ebay) ? One major advantage is that in a situation where there are several photographers (eg: wedding) optical flash triggers are pretty useless but how about in a studio setting for portraits ?

Thanks

[PacAce]

I was reading up about triggering flashes on this post (http://photography-on-the.net/forum/showthread.php?t=528785)and I have a few queries

1) if I trigger flashes using PW, Skyports or the Cactus triggers then I would need to set the flashes on manual mode and that ETTL would not work ?

2) If I use an ST-E2, the information sent to off camera flash is based on ETTL? From what I understand of ETTL, this is not possible as the camera would not have any information about where the off-camera flash is placed. So, effectively if using off-camera flashes, ETTL does not work - is that right ?

3) What would be the difference / advantages of using cactus triggers as opposed to cheap optical slave flash triggers ($5-$6 on ebay) ? One major advantage is that in a situation where there are several photographers (eg: wedding) optical flash triggers are pretty useless but how about in a studio setting for portraits ?

Thanks

1) That is correct. With an RF remote triggering setup you would lose all ETTL functionality.

2) No, it is not. The master flash or the ST-E2 would be the on-camera "flash" that talks to the camera. The master would then convey any ETTL instructions to the slaves so, in essence, all the off-camera slaves would be working in ETTL mode even though they're not directly attached to the camera.

3) RF remote triggering works much better outdoors than optical or IR remotes do. They also have a longer "reach".

[jpwone]

1. Correct. Flashes in manual and no Ettl.

2. Incorrect. Ettl triggers a pre-flash and calculates the actual flash required from that. So, St-E2 on camera controlling one or more 430EX, 550EX, 580EX will work fine under Ettl control. Camera tells ST-E2 to trigger remote flashes to generate pre-flash. Camera picks up pre-flash result via lens and calculates flash requirement. Camera passes data to ST-E2 to trigger remote flashes.

3. optical slaves are a real pain the moment you take them out of a controlled environment. The cactus triggers are fine for what they are but having travelled that road I now have the Skyports. In a studio with short ranges the cactus solution is fine but my own experience was inconsistent triggering even over relatively short ranges indoors and very poor performance outdoors.

[riyazi]

Thanks Pacace and JPWOne.

Interesting - so in effect, the ST-E2 works like a glorified optical trigger.

For my purposes it looks like getting Optical triggers would work best - and more importantly would be the cheapest option as well. My purpose would be - a controlled studio type environment for portraits mainly. If I ever use off camera flash outside, it will be for short distances so I dont have a problem with the limitations of the optical trigger for that.

At the moment, I have a 430EX which I mount on the camera (40D) and use a generic flash on a optical trigger as an off camera flash. When I press the * (exposure) button, a preflash is emitted and the exposure is based on the flash from the 430EX plus the optically triggered flash - so effectively, ETTL flash metering. The only issue I have with this is that I need to press the * button to get the exposure then take the shot with the shutter button. So to get one single image I need to trigger both flashes twice - once with the * and again with the shutter button. It also takes twice as long for each image becos of flash recharge time. I assume I can avoid this by setting off preflash, which makes it a manual control based flash system - similar to using the cactus triggers.

Please let me know whether any of the above makes sense or not and whether I am right. I have no money to spend on skyports let alone PWs so was thinking of getting the cactus triggers - but I think it would be a waste of money considering my requirements.

[PacAce]

Thanks Pacace and JPWOne.

Interesting - so in effect, the ST-E2 works like a glorified optical trigger.

For my purposes it looks like getting Optical triggers would work best - and more importantly would be the cheapest option as well. My purpose would be - a controlled studio type environment for portraits mainly. If I ever use off camera flash outside, it will be for short distances so I dont have a problem with the limitations of the optical trigger for that.

At the moment, I have a 430EX which I mount on the camera (40D) and use a generic flash on a optical trigger as an off camera flash. When I press the * (exposure) button, a preflash is emitted and the exposure is based on the flash from the 430EX plus the optically triggered flash - so effectively, ETTL flash metering. The only issue I have with this is that I need to press the * button to get the exposure then take the shot with the shutter button. So to get one single image I need to trigger both flashes twice - once with the * and again with the shutter button. It also takes twice as long for each image becos of flash recharge time. I assume I can avoid this by setting off preflash, which makes it a manual control based flash system - similar to using the cactus triggers.

Please let me know whether any of the above makes sense or not and whether I am right. I have no money to spend on skyports let alone PWs so was thinking of getting the cactus triggers - but I think it would be a waste of money considering my requirements.
Wouldn't it be much more convenient to just set the 430EX to manual mode so that you won't need to deal with the preflash? Besides, with the preflash being fired, the camera really isn't determining the correct flash exposure unless you are someone overriding what the camera has calculated by using FEC. You see, when you fire the preflash with the "* button, it will also fire the off-camera flash at whatever power level you have it set to. This will make the camera under rate the amount of flash the 430EX will need to emit to properly expose the picture. If the off-camera flash is your primary light source, then the 430EX underexposing isn't really going to be an issue since it's just being used as fill. But if that's the case, then why bother with ETTL in the first place? Setting it to manual mode will be less of a hassle for you, then.

[riyazi]

The pre-flash is actually not much of a problem - in fact it helps me get a properly exposed pic. Like you inferred, I use the off camera flash as the main light source and use the 430EX on the camera as fill light. The off camera flash is placed to the side and above or right above the subject. This helps even lighting especially for my product photography. And it also helps with my newbie status :)

Actually I am already taking steps to do what you suggested - going to manual mode on the flash. I want to remove the 430EX and use that as a off camera flash - this is why I was considering cactus triggers. But I realise that getting just an optical trigger will help me more than getting cactus triggers. But I need to do a lot experimenting to be more comfortable with the flash on manual mode.

[PacAce]

The pre-flash is actually not much of a problem - in fact it helps me get a properly exposed pic. Like you inferred, I use the off camera flash as the main light source and use the 430EX on the camera as fill light. The off camera flash is placed to the side and above or right above the subject. This helps even lighting especially for my product photography. And it also helps with my newbie status :)

Actually I am already taking steps to do what you suggested - going to manual mode on the flash. I want to remove the 430EX and use that as a off camera flash - this is why I was considering cactus triggers. But I realise that getting just an optical trigger will help me more than getting cactus triggers. But I need to do a lot experimenting to be more comfortable with the flash on manual mode.
Aren't you already using the main, off-camera flash in manual mode? Or is that set the auto mode?

[riyazi]

:) Nope its on manual mode - but by using the preflash / * button approach, I have eliminated the need for experimenting and incorrect exposure as the camera does that for me automatically - as long as the off camera flash is not too close or far. Especially since the 430EX has enough power to provide proper fill light for a properly exposed pic.

By moving the 430EX off camera and taking off preflash, I will need to look at flash positions, flash power, diffusing, etc differently to get a properly exposed picture. And it will depend on how I set things manually. Or thats way I see it.

[PacAce]

:) Nope its on manual mode - but by using the preflash / * button approach, I have eliminated the need for experimenting and incorrect exposure as the camera does that for me automatically - as long as the off camera flash is not too close or far. Especially since the 430EX has enough power to provide proper fill light for a properly exposed pic.

By moving the 430EX off camera and taking off preflash, I will need to look at flash positions, flash power, diffusing, etc differently to get a properly exposed picture. And it will depend on how I set things manually. Or thats way I see it.

But I thought you said that the off-camera flash was your main light and your on-camera flash was just being used for fill. If that were the case, then surely you would have set up the off-camera flash so that it would give you the proper main light exposure since getting that right would be more important than getting the fill light right (as long as the fill light is just that and doesn't overwhelm the main light).

[FlashZebra]

I was reading up about triggering flashes on this post (http://photography-on-the.net/forum/showthread.php?t=528785)and I have a few queries

1) if I trigger flashes using PW, Skyports or the Cactus triggers then I would need to set the flashes on manual mode and that ETTL would not work ?

2) If I use an ST-E2, the information sent to off camera flash is based on ETTL? From what I understand of ETTL, this is not possible as the camera would not have any information about where the off-camera flash is placed. So, effectively if using off-camera flashes, ETTL does not work - is that right ?

3) What would be the difference / advantages of using cactus triggers as opposed to cheap optical slave flash triggers ($5-$6 on ebay) ? One major advantage is that in a situation where there are several photographers (eg: wedding) optical flash triggers are pretty useless but how about in a studio setting for portraits ?

Thanks
You may also want to read this generous post by CurtisN:

http://photography-on-the.net/forum/showthread.php?t=308108

Enjoy! Lon

[Titus213]

Any chance we could get a sample picture using this combination of flashes?

The 430EX on the camera is measuring the available light with the pre-flash. That available light includes the remote. If you just pressed the shutter button the pre-flash from the 430Ex would trip the remote flash and it wouldn't recycle fast enough to take the picture. By pressing the * button you are giving the off camera flash time to recycle. Clever but I would think it would eventually cause problems with improper lighting.

[riyazi]

But I thought you said that the off-camera flash was your main light and your on-camera flash was just being used for fill. If that were the case, then surely you would have set up the off-camera flash so that it would give you the proper main light exposure since getting that right would be more important than getting the fill light right (as long as the fill light is just that and doesn't overwhelm the main light).

Leo - I am not sure I understand your confusion as you seem to be knowing more about my setup than myself :) You are right the - off camera flash is the main light and is set at a position which doesnt make the subject too bright. The 430EX provides fill light which evens out the lighting and corrects exposure. Without the 430EX firing, I assume (as the 430EX or atleast camera flash HAS to fire to trigger the off camera flash I cant test this) that the light provided by the off camera flash would be harsh with deep shadows and incorrect exposure. My point is that the combination of the flashes even out the lighting making it easier for me to get the image. Using only one of the flashes would require me to get in to full manual mode - moving flash, diffusing, experimenting etc.

You may also want to read this generous post by CurtisR:
http://photography-on-the.net/forum/showthread.php?t=308108
Enjoy! Lon

Thanks Lon - I DID read that thread some time ago - but I think I need to revisit again - thanks for the reminder

Any chance we could get a sample picture using this combination of flashes?
At the moment I dont have any pics of the setup, but will try to get some during the weekend and post here.


The 430EX on the camera is measuring the available light with the pre-flash. That available light includes the remote. If you just pressed the shutter button the pre-flash from the 430Ex would trip the remote flash and it wouldn't recycle fast enough to take the picture. By pressing the * button you are giving the off camera flash time to recycle. Clever but I would think it would eventually cause problems with improper lighting.
EXACTLY what I am doing and acheiving. So far, I have been able to get good results but now that I am thinking of moving the 430EX as an off camera flash, I might have probs with improper lighting so experiments are in order. But with regard to the triggers, the optical trigger still seems to be the option for me.