Off-camera E-TTL

[Iron Flatline]

I've been shooting my strobes manually, but am trying to use the E-TTL occasionally. I'm not sure how it all works. I use PocketWizards (the new smaller kind) to trigger the unit - I know the camera meters through the lens, but does the flash unit do a separate distance calculation, or does the camera assume the flash about equidistant from the subject? I'm not waiving it around wildly, my arm is only so long, but sometimes working close in the distances matter.

Also, I can't seem to stop down the flash power on the unit while set to E-TTL. So do I do it on the camera? Or do I shoot in Tv and then dial in a little more aperture?

580 EX IIs on 1Ds Mk III or a 5D.

 

[Big Mike]

I'm not sure if the camera/flash knows or calculates the distance. I think that just measuring the light that comes back TTL is enough for it to work.

I don't remember for sure, but I think that to adjust the power of the slave, you need to adjust the power (or ratio) of it's 'group' from the master unit. When using multiple flashes with Canon's wireless system, it puts the flashes in into groups. 'I think' that the ST-E2 can control 2 groups while the 580EX can control three. 'I think' that the master unit is one group (others could be added)....so to adjust the power of the slave flash, you need to adjust the ratio of that group to the master group (I think they are letters...A, B, C)

 

[Brian L]

First.... You are correct. The camera meters for exposure. Second what pockets wizards are you using? The mini tt1 and flex tt5 support ettl through radio wave. If your using that setup then you will need as stated by the other guy sorry I am typing the reply and can't see your name, that you will need a master flash on top of your mini tt1 mounted to the camera or you can use a flex tt5 mounted to the camera as a transmitter. If you trying to use ettl with the plus 2 system or before models those are just manual flash triggers and setting the flashes to maunal for power output will be made by you and not sent via radio due to them being only manual triggers and not supporting ettl.

Here they are using the canon system.



They don't support nikon yet.

and since the mini tt1 and flex tt5 can be both mounted on the camera as the transmitter and support ettl for your system, it makes your camera think there is a flash there. Since that is the case only control you get is normal as in you can exposure compensate ev + or - do control off camera flash power. which you will see in this video. however if your using a on camera flash for a master then all the controls you set on that flash such as power, ev + or - will go to the slave flash via ettl.



I just am getting into the system and deciding between the radio poppers px system or the pocket wizards. doing lots of reading and learned a lot bout the 2 system in the last week. Hope this helps.

 

[Brian L]

and that would be BIG MIKE above me. That is the guy I was referring too.

 

[ssnxp]

Thanks for the videos/info Brian! I'm in the same boat (not buying yet, but doing research) and the videos were helpful. Let us know what you decide on.

 

[Brian L]

Ya man no problem. Well I just did more research and finding with the pocket wizards mini tt1 and flex tt5 then operate on a freq range of 300.000mhz. This is bad because the canon 580ex II flashes give off some interference at that range and are causing the ettl not to work up to the range of 1200 feet. Pocket wizards fix for that is a rf block material or sock to go over my flashes. I don't know if I like that idea so much. Falling toward getting another 580ex II and the radio popper px system.

 

[ssnxp]

Ya man no problem. Well I just did more research and finding with the pocket wizards mini tt1 and flex tt5 then operate on a freq range of 300.000mhz. This is bad because the canon 580ex II flashes give off some interference at that range and are causing the ettl not to work up to the range of 1200 feet. Pocket wizards fix for that is a rf block material or sock to go over my flashes. I don't know if I like that idea so much. Falling toward getting another 580ex II and the radio popper px system.

Thanks for the info! Man, I was hoping the wizards would come out on top, the Pluss II and MultiMAX just look so awesome.

 

[Iron Flatline]

Would you shoot E-TTL at that distance? I guess it would make sense, hard to climb up there each time to adjust the unit manually...

 

[Brian L]

Would you shoot E-TTL at that distance? I guess it would make sense, hard to climb up there each time to adjust the unit manually...

I don't see my self shooting that distance but its nice to know that you can. The radio poppers system shoots just as far. I guess if you want to be creative.