420EX as optical slave issues

[sanjay_bhave]

My 420EX works fine as optical slave with Canon on-camera flash as the trigger. However it does not fire with Yongnuo 600EX-RTII. I am thinking that the optical sensor of the 420EX should sense any flash and be triggered to fire. Am I not correct in thinking so?

Thanks

[MikeSowsun]

No, the Canon 420EX can not operate as a simple optical slave. In fact, there are no Canon brand flashes that can operate as simple optical slaves. (responding to any flash of light)

The Canon 420EX can only respond to Canon proprietary coded optical signals from a Canon Master flash unit like a 580EX II or any other Canon compatible master flash unit.   The Yongnuo 600EX-RT II can be a master flash compatible with both the Canon and Nikon proprietary flash systems, so I expect you have not set it up correctly. 

The older Yongnuo 600EX-RT has only a radio master slave capability while the Yongnuo 600EX-RT II has both Canon proprietary optical and radio master/slave capability.  Make sure you are using the optical system and not the radio system.

[sanjay_bhave]

Thank you very much MikeSowsun for your suggestions. After seeing your message I tried out several changes to the YN-600EX-RTII settings but have not been successful in firing the 420EX in optical slave mode. I will keep trying some more.

Thanks again

[diverhank · Accepted solution]

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@sanjay_bhave wrote:

Thank you very much MikeSowsun for your suggestions. After seeing your message I tried out several changes to the YN-600EX-RTII settings but have not been successful in firing the 420EX in optical slave mode. I will keep trying some more.

Thanks again

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1.  On the 600EX, make sure it's in the Master Mode - Optical instead of Radio.  I don't have the Yongnuo YN-600EX-RTII but if it works like the Canon, the symbol for optical is a lightning bolt , not an antenna with concentric circles.

2. Make sure on both the 600EX and the 420EX, the channel number is the same.

3. Make sure the 600EX is in ETTL and not Manual or MULTI.  The 420EX doesn't like M and MULTI on the Master

4. Make sure the 420EX switch is turned to SLAVE.

Hopefully it will work for you. Good luck.

[sanjay_bhave]

Thank you diverhank!! The setting you suggested worked to allow the 420EX as optical slave while using the 600EXII as master. 

Thanks much

[sanjay_bhave]

Diverhank

I was hoping to using the remote flash controller to fire the Yongnuo flashes and in turn trigger the 420EX. However to fire the Yongnuo's they would have to be set as slaves and this does not trigger the 420EX. Is there a way you might know to do this.

Thank you for your previous suggestion.

Sanjay

[diverhank]

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@sanjay_bhave wrote:

Diverhank

I was hoping to using the remote flash controller to fire the Yongnuo flashes and in turn trigger the 420EX. However to fire the Yongnuo's they would have to be set as slaves and this does not trigger the 420EX. Is there a way you might know to do this.

Thank you for your previous suggestion.

Sanjay

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The YN600EX-RT II as a slave will not be able to set off the 420EX.  An optical master can set off multiple slave flash units.  You can set both the YN600EX-RT II and the 420EX as slaves and they will all work.

You can do the following to get this to work:

1.  Use one of the YN600EX-RT II as an optical master (remember the lightning bolt).  Or you can use a flash controller such as the ST-E2.  For either one, set it to Optical Master, make sure channel is the same for all units.  Also make sure it's not in M or MULTI.

2. Set the other YN600EX-RT II and the 420EX as optical slaves (lightning bolt).

You can set each of the slaves to a different group (you're allowed 3 groups) so you can individually control the flash output.  Here is a link to a Canon guide for optical wireless set up for the Canon 600EX-RT.  This is pretty much applicable to the Yongnuo unit also.

https://learn.usa.canon.com/app/pdfs/quickguides/CDLC_Speedlite_600EX-RT_Optical_Setup_QuickGuide.pd...