Pocket Wizards and TTL

[toddlaffler]

Can anyone verify this for me? I want to have my 580EX in the hotshoe on my 5D, then have a pocket

wizard connected to my camera (via PC Port?) which will trigger a remote flash on a stand, that flash being

set to manual.

 

Can I retain the E-TTL function of the on camera flash while still triggering a remote flash set to manual

mode, to be used as a kicker, or room light for instance?

 

According to the online PDF manual there is a section about using TTL flash in this manner, but was just

wondering if anyone has actually done it, and does it actually work?

 

Lastly, can someone suggest a good way of mounting the camera connected pocket wizard? It seems it

would be awkward to have the PW connected to the camera (with that big rubber "door" opened) and then

velcro the PW to the flash. I like to bounce flash so am always twisting the flash head around and back and

forth etc. I'm concerened the cord will not be long enough or will tug etc. Any ideas are much appreciated.

 

Thanks

 

Todd

 

PS, just thought of something else. If I can still use E-TTL on the camera mounted flash, can I easily

(remotely) choose not to fire the slave?

[ellis_vener_photography]

You can retain TTL, but it's gonna be fooled by the light from the slaved flash.

[dave_holland]

AS Ellis alluded to, ETTL will not 'see' your PC slaved flash, because it won't go off when the ETTL preflash goes off. So, when ETTL calculates the needed output for the on-camera flash, it disregards the unseen output from your hardwired flashes. This might not be a problem with kicker lights, but would be a huge problem with more dominant lighting. So, when I use a mix of lights as you are doing I shoot in all manual to keep things simple. It's easier than it seems.

 

Dave

[toddlaffler]

Thanks for the info. I was thinking of using the slave as a rim light perhaps or to light up

dark areas of a room that won't be lit from the on camera bounced flash. I wasn't thinking

of using it as a dominant light source by any means.

 

At a reception I normally shoot in manual mode on the camera, picking all my settings,

and then let the flash determine the proper light output. The reason I don't shoot with the

flash in manual mode as well is because when bouncing off of ceilings, I usually find that

as you walk around to different spots around a large ballroom that the light bounces

differently depending on your position. Sometimes there is a small obstruction, or a

chandelier or something in the way, so I don't see how a set it and forget approach could

be consistent. Maybe you can elaborate on that.

 

Also, can anyone chime in on the reliability of the PC connection on the 5D? I have heard it

can be unreliable when using PWs.

 

Thanks

[frank_skomial]

Looks like you have good understanding of the problem, with little caution and paying attention, you should be able to use ETTL automation needed in dynamicaly changing environment, with simulteous use of manual non-TTL flashes working to your advantage.

 

The light determination in ETTL (or iTTL) is done during preflashes (when non-TTL flashes do not fire), and the ETTL cannot be fooled by anyone at this time, providing correct light output later during exposure time when the shutter is open.

 

The ETTL flash is unaware of presence or power of any external flash fired by PocketWizards or cables. Can only trigger flashes connected like that, but cannot control the output from them. Since other flashes were not taken into light determination during pre-flashes, therefore over exposure is likely to happen, but you can prevent that.

 

The ETTL flash is not fooled, and always provides alone correct amount of light regardles if any other flash exists or not - giving you chance to use all the flashes together.

 

(The only time when ETTL/iTTL could get fooled - computed wrong amount of light - could be if any non-TTL flash was fired during pre-flashes time, if connected via non-digital optical slave. PocketWizard or cable connection precludes this case here, right?)

 

The safest, (but not the only use), is to bouce remote flashes of white walls or ceilings, and the chance that your main ETTL flash could be overpowered by the manual flashes will be reduced or nearly eliminated.

 

I frequently use Nikon CLS system (perhaps same/close to Canon ETTL system ?), with 2 studio 1800 Wattseconds flashes located strategically, and out of human traffic if possible.

The studio flashes are set to max or fractional power (depends on the room size, reflectivity of ceiling/walls, etc), and triggered via Pocket Wizards. With 2 large flashes providing flash ambient lighting, single flash in ETTL/iTTL provides correct amount of main flash directed at the subject.

 

I also experimented with 3 iTTL flashes, all providing direct to subject lighting from different angles with help of assistants, in CLS automated exposure system, with 2 manual studio flashes bounced and triggered via PocketWizards. Adjusting higher level of ambient lighting from studio flashes made use of additonal iTTL/CLS flashes unecessary, and less disturbing to people, and single photographer does not need assistants.

[alec_myers]

I do this quite a lot.

 

"Can I retain the E-TTL function of the on camera flash while still triggering a remote flash set to manual mode, to be used as a kicker, or room light for instance?" - Yes, you can.

 

"does it actually work?" Yes.

 

"Lastly, can someone suggest a good way of mounting the camera connected pocket wizard? It seems it would be awkward to have the PW connected to the camera (with that big rubber "door" opened)"

 

I use a cheap and cheerful flash bracket to put the PW on, with a cable, and leave the 580 on the hot shoe. With the 70-210 lens yes the whole rig is big, bulky and heavy. I used to use velcro to attach the PW to the side of the camera, but it kept falling off, getting caught, getting pulled off by the cable etc.

 

"If I can still use E-TTL on the camera mounted flash, can I easily (remotely) choose not to fire the slave?" Yes, just flip the off switch on the PW.

 

In general using two flashes like this works well when the slaved flash is away from the subject, in other words, in situations where without the hot-shoe mounted flash your subject will be underexposed. If you're moving around in an environment where your slave flash stays fixed then you can easily switch off the hotshoe flash and switch to manual exposure when close to it. When you move away from it you can go back to Av (or stay on manual as you prefer) and switch on the 580.

 

I tend to switch off the slave flash less often, but it's easy enough.

[picturesque]

While I don't use Pocket Wizards, I do use the 580EX in ETTL on the camera and manual slaved flashes off camera. It works in practice, even for a manual, off camera main light with the on camera acting as fill. I just dial in -1 or so flash comp on the on camera flash.

 

Others have answered your questions so my only other comment is about mounting the transmitter unit to the camera. I found that using a cord into the PC socket was problematic because it twisted and turned and caused occasional misfires. I use the following cheap bracket to basically clamp the PC cord plug into the camera's socket by friction/pressure of the bracket. It immobilizes the plug. You also have two cold shoes to put the transmitter or other accessory, as well as have a handy place to grip the camera. I have seen others use a plain straight bracket or cannibalized part of old flash brackets.

 

http://www.bhphotovideo.com/c/product/131401-REG/General_Brand__Right_Angle_Bracket_with.html