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Phottix Odin TTL (& remote manual) Radio trigger for Canon Dual Control of twinned on-axis 550Ex speedlites
Published November 26th 2011.
Two 550Ex speedlites controlled simultaneously by one Phottix Odin radio receiver. Dual control. Thats TTL or M (remotely adjusted) and either with HSS or SCS!
Warning: This is a non-standard configuration. I am not recommending this use of Odin receivers. If you try this, it is entirely at your own risk. This configuration does not seem to work with 580ExIIs!
I'm still in early testing (as at 26-11-2011), but so far I have got perfect remote Manual flash power fraction control from the Odin TCU in the cam's hot-shoe. The 2 Ex units respond in parallel. The two speedlites - both 550Exs - are initially setup idendentically. The flash-heads are both up in a bounce orientation - wide panels both retracted. This may only apply to 550Exs. This configuration does not seem to work with 580ExIIs - possibly, it only works with pre-'II' series Ex speedlites. I have not tested all Ex speedlites - my guess would be that the pair must be identical twins for this to work. Remember that the 550Exs pre-date all the 'II' series Ex speedlites, so there are potentially a lot of variables to check.
The TTL cord is specifically 'ishoot' brand, their dual cord - and a recent batch (Nov '11). I tried this originally with a Yn dual cord & it seemed not to work. It may turn out that the 'ishoot' version is the only one of the 'dual' cords to work for this configuration. Note that there are several different versions of these 'dual' style TTL cords, which already differ from OC-E3 clones. The 'ishoot', the Yn, the Pixel and the Nissin version all differ externally and probably internally too.
Link: Feb '15:
www.ebay.com/itm/iShoot-2-5m-Flash-SYNC-E-TTL-Off-Camera-...
My logic for using 550Exs was first that they are less than half the price of a new 580ExII, in fact £90 to £130, they are pretty powerfull and they accept external power packs. So this configuration potentially offers the maximum gain for the minimum cost/risk.
Always turn on both speedlites before turning on the Rx unit. I only reconfigure the speedlites (deploy wide panel etc) with both the speedlites and the Rx temporarily switched off. Switch off the Speedlites before switching off the Rx.
This configuration is also good for TTL too - that's with FEC by group & globally - all with the option of HSS! The camera's flashmetering is best set to 'Average' for flash rather than 'Evaluative' (done in cam's Cfns or in the cam's flash menus - not from the camera's top-plate!). Tx to 'stripealipe' for this info - applies at least to the original release firmware (Edit: This restriction only applies to the on-release - later versions remove it). This is running very well indeed from both a 20D & a 7D. The modeling light function, controlled from the Odin TCU, also serves as focus assist. Easy with a little practice!
So, with Phottix Odins, either very nearly twice the power* or half the recycle time - all with a considerable cost saving - preserving remote power adjustment - Manual &/or TTL (& HSS for both) - from the TCU/camera unit. With Odins, M power fractions or FEC under ETTL, are adjusted by Group, directly from the TCU's screen - much quicker than having to delve into the camera's flash menu screens!
*: Not quite twice the power because I tend to splay the flash-heads slightly, giving very much better spread within most modifiers. So it's very much prettier light with smooth shadow transitions with quicker recylcing and/or nearly an extra stop of light.
Edit at 10-12-2011: Leaving TTL to one side, for metered manual flash, albeit (in-cam) metered flash, so far I've got two options. One is to use a variation of Chuck Gardner's white terry towelling reflected flash technique. I think you would need to use the 'only-just-clipping-white' end-point on a dummy shot taken with the white towelling in the subject position. With a bit of thought this can be used for ratios too.
The second option is based on an Expodisc or close clone - the uniform white type. This turns your cam's chip into an incident 'capture-flash' flash-meter and works well maybe sorting WB along the way. You would need to determine your own 'zero point' on your histogram specific to the transmissibility of your Expodisc or clone. Yep, they can be made to work. Likewise Olivier's idea of combining SCS with a long shutter speed, allowing time to reprime the meter before the capture-flash, works too. It assumes rather dim ambient levels and that you revert to a more typical SS for the actual capture - but it works too.
Edit: There are two extra options for using an external flashmeter in an Odin network operating in M flash. See this later post: www.flickr.com/photos/layeroption/11755249874/in/photostream
Edit at 18-12-2011: Being a certifiable, card-carrying strobist uber-nerd, I checked out a second 'ishoot' brand 'dual' ETTL cord with two other 550Exs - and - it worked in this configuration too! So, the warning still applies but it wasn't a fluke. Did I then interpose my Flashzebra 20ft OC-E3 clone on the distal speedlite end? Yep, that worked too - v rarely useful, but it would keep the camera/TCU un-tethered even if you were one Odin Rx short of a full load.
In fact I then daisy-chained 2 'ishoot' dual cords together (symetrically) & yes, 3 550Exs work as one together & respond in both M & TTL as they should. Sweet!
Edit at 04-01-2012: From my padded cell - 3 'ishoot' thingeys - X4 550Exs: Yes!
(My Yn 'dual' ETTL cord definitely does not work like this. And Elv says that Phottix's own 'dual' cord does not work for this configuration either.)
N.B. All of this applies using 550Exs with the original release Phottix Odin firmware. Update 24-08-12: This works with 550Exs and Firmware version 1.2 - Oh yes! - I like these triggers.
Edit at 30-01-2012: Many many hundred pops, scores of reconfigurations; zero issues! That goes for my other Odin Radio Rxs in use controlling either 580ExIIs or 550Exs. That's usually just one Ex to one Rx!
Edit: These Dual TTL cords from 'Ishoot' are becoming harder to find. Try Ebay searches under 'dual ttl cord'. Good luck.
Edit: 2-8-13: This post refers to the original hardware version 'Odin for Canon'. I updated to firmware v1.2 c August 2012. It seems that Phottix migrated to hardware type 'Odin 1.5 for Canon' some time ago.
Edit: 20-09-13: With the Mitros+ (Mitros Plus) just announced, I guess a pair of those could be used without the Dual cords & external Odin Rx. Similar functionality and beans at about X3 the cost - but tempting!
Phottix Odin TTL (& remote manual) Radio trigger for Canon Dual Control of twinned on-axis 550Ex speedlites
Published November 26th 2011.
Two 550Ex speedlites controlled simultaneously by one Phottix Odin radio receiver. Dual control. Thats TTL or M (remotely adjusted) and either with HSS or SCS!
Warning: This is a non-standard configuration. I am not recommending this use of Odin receivers. If you try this, it is entirely at your own risk. This configuration does not seem to work with 580ExIIs!
I'm still in early testing (as at 26-11-2011), but so far I have got perfect remote Manual flash power fraction control from the Odin TCU in the cam's hot-shoe. The 2 Ex units respond in parallel. The two speedlites - both 550Exs - are initially setup idendentically. The flash-heads are both up in a bounce orientation - wide panels both retracted. This may only apply to 550Exs. This configuration does not seem to work with 580ExIIs - possibly, it only works with pre-'II' series Ex speedlites. I have not tested all Ex speedlites - my guess would be that the pair must be identical twins for this to work. Remember that the 550Exs pre-date all the 'II' series Ex speedlites, so there are potentially a lot of variables to check.
The TTL cord is specifically 'ishoot' brand, their dual cord - and a recent batch (Nov '11). I tried this originally with a Yn dual cord & it seemed not to work. It may turn out that the 'ishoot' version is the only one of the 'dual' cords to work for this configuration. Note that there are several different versions of these 'dual' style TTL cords, which already differ from OC-E3 clones. The 'ishoot', the Yn, the Pixel and the Nissin version all differ externally and probably internally too.
Link: Feb '15:
www.ebay.com/itm/iShoot-2-5m-Flash-SYNC-E-TTL-Off-Camera-...
My logic for using 550Exs was first that they are less than half the price of a new 580ExII, in fact £90 to £130, they are pretty powerfull and they accept external power packs. So this configuration potentially offers the maximum gain for the minimum cost/risk.
Always turn on both speedlites before turning on the Rx unit. I only reconfigure the speedlites (deploy wide panel etc) with both the speedlites and the Rx temporarily switched off. Switch off the Speedlites before switching off the Rx.
This configuration is also good for TTL too - that's with FEC by group & globally - all with the option of HSS! The camera's flashmetering is best set to 'Average' for flash rather than 'Evaluative' (done in cam's Cfns or in the cam's flash menus - not from the camera's top-plate!). Tx to 'stripealipe' for this info - applies at least to the original release firmware (Edit: This restriction only applies to the on-release - later versions remove it). This is running very well indeed from both a 20D & a 7D. The modeling light function, controlled from the Odin TCU, also serves as focus assist. Easy with a little practice!
So, with Phottix Odins, either very nearly twice the power* or half the recycle time - all with a considerable cost saving - preserving remote power adjustment - Manual &/or TTL (& HSS for both) - from the TCU/camera unit. With Odins, M power fractions or FEC under ETTL, are adjusted by Group, directly from the TCU's screen - much quicker than having to delve into the camera's flash menu screens!
*: Not quite twice the power because I tend to splay the flash-heads slightly, giving very much better spread within most modifiers. So it's very much prettier light with smooth shadow transitions with quicker recylcing and/or nearly an extra stop of light.
Edit at 10-12-2011: Leaving TTL to one side, for metered manual flash, albeit (in-cam) metered flash, so far I've got two options. One is to use a variation of Chuck Gardner's white terry towelling reflected flash technique. I think you would need to use the 'only-just-clipping-white' end-point on a dummy shot taken with the white towelling in the subject position. With a bit of thought this can be used for ratios too.
The second option is based on an Expodisc or close clone - the uniform white type. This turns your cam's chip into an incident 'capture-flash' flash-meter and works well maybe sorting WB along the way. You would need to determine your own 'zero point' on your histogram specific to the transmissibility of your Expodisc or clone. Yep, they can be made to work. Likewise Olivier's idea of combining SCS with a long shutter speed, allowing time to reprime the meter before the capture-flash, works too. It assumes rather dim ambient levels and that you revert to a more typical SS for the actual capture - but it works too.
Edit: There are two extra options for using an external flashmeter in an Odin network operating in M flash. See this later post: www.flickr.com/photos/layeroption/11755249874/in/photostream
Edit at 18-12-2011: Being a certifiable, card-carrying strobist uber-nerd, I checked out a second 'ishoot' brand 'dual' ETTL cord with two other 550Exs - and - it worked in this configuration too! So, the warning still applies but it wasn't a fluke. Did I then interpose my Flashzebra 20ft OC-E3 clone on the distal speedlite end? Yep, that worked too - v rarely useful, but it would keep the camera/TCU un-tethered even if you were one Odin Rx short of a full load.
In fact I then daisy-chained 2 'ishoot' dual cords together (symetrically) & yes, 3 550Exs work as one together & respond in both M & TTL as they should. Sweet!
Edit at 04-01-2012: From my padded cell - 3 'ishoot' thingeys - X4 550Exs: Yes!
(My Yn 'dual' ETTL cord definitely does not work like this. And Elv says that Phottix's own 'dual' cord does not work for this configuration either.)
N.B. All of this applies using 550Exs with the original release Phottix Odin firmware. Update 24-08-12: This works with 550Exs and Firmware version 1.2 - Oh yes! - I like these triggers.
Edit at 30-01-2012: Many many hundred pops, scores of reconfigurations; zero issues! That goes for my other Odin Radio Rxs in use controlling either 580ExIIs or 550Exs. That's usually just one Ex to one Rx!
Edit: These Dual TTL cords from 'Ishoot' are becoming harder to find. Try Ebay searches under 'dual ttl cord'. Good luck.
Edit: 2-8-13: This post refers to the original hardware version 'Odin for Canon'. I updated to firmware v1.2 c August 2012. It seems that Phottix migrated to hardware type 'Odin 1.5 for Canon' some time ago.
Edit: 20-09-13: With the Mitros+ (Mitros Plus) just announced, I guess a pair of those could be used without the Dual cords & external Odin Rx. Similar functionality and beans at about X3 the cost - but tempting!