6d external flash ???

ralphbrunt · May 29, 2017

hello, my girlfriend is about to give birth to our son, that being said I would like to go to the beach and shoot her before that. I have a 6d and a 430 ex2 that I need to fire externally. I have used the search function and read so many different things that my head is swimming.
I would like to use the canon Canon ST-E3-RT but, I am concerned that my 430 ex2 is fired from light and not radio freq
and I may want it behind me pointed at the sun and I don't think that will work? I am not opposed to buying a good set up I just don't know what will work best.. please help
thanks ralph

TCampbell · May 30, 2017

The Speedlite 430EX II can only be used via the "optical" trigger ... the ST-E3-RT is a "radio" trigger and has no optical capability.

But on-camera flash is typically used as a "fill" flash to help pump a little light into otherwise very dark and harsh daytime shadows. That "fill" can be on-camera (no need to use off-camera). When going off-camera, then you usually want to soften the transitions from light to shadow by modifying the light so that it comes from a "broad" light source and not a pin-point light source. Soft-boxes are popular for this. Even a large reflector (but that usually requires a person to hold the reflector to direct the light).

Daytime light conditions will basically require that you shoot at high f-stops values (e.g. ISO 100, f/16 & 1/100th sec exposure is the basic exposure for the "sunny 16" rule for mid-day full-sunlight (no shadow, no overcast.) Your 6D cannot use a flash at any shutter speed faster than 1/160th sec exposure UNLESS you enable "high speed sync" mode on the flash. This means even f/11 is too much (that would require that you shoot at 1/200th which is above your camera's maximum flash-sync speed).

If you enable high-speed sync mode on your 430EX II then you can use lower f-stops (or shoot with a natural density filter such as 3-stop (aka "ND 0.9" filter) which would darken the exposure by three full stops (that would let you shoot at f/5.6 without having to enable high-speed sync mode).

If you shoot nearer to sunset (aka "the golden hour" then the light will be reduced and this will let you open up the aperture slightly). But in this situation you're stuck with an amber colored sunlight and a "white" colored flash. The solution here is to put a gel (colored clear plastic that matches the color of the sun). These gels are usually referred to as a "CTO" (color temperature orange) gel. The "color temperature" means it's being used to change the white balance "temperature" to match the color of the sun at sunset.)

beagle100 · May 30, 2017

ralphbrunt said:
hello, my girlfriend is about to give birth to our son, that being said I would like to go to the beach and shoot her before that. I have a 6d and a 430 ex2 that I need to fire externally. I have used the search function and read so many different things that my head is swimming.
I would like to use the canon Canon ST-E3-RT but, I am concerned that my 430 ex2 is fired from light and not radio freq
and I may want it behind me pointed at the sun and I don't think that will work? I am not opposed to buying a good set up I just don't know what will work best.. please help
thanks ralph

I believe that uses "RF" radio frequency and wouldn't be affected by the light. But for many purposes a cheap Yongnuo manual RF flash trigger works fine, like the yongnuo 602, 603, etc. -- on ebay for $15