PC vs Hotshoe connectors for off-camera flash

I have a question regarding the connection method for an external flash. I am using a 40D, with a 580 ex2 mounted on a bracket above the camera. The cable that I am using to attach the 2 goes from the PC port on the camera to a "household to hotshoe" adapter, that adapter then attaches to the bracket and the flash.

I am shooting night sports under stadium lighting, trying to use the flash to stop motion on the shots. The camera is set to manual, at an exposure where without the flash, the subjects are barely visible (I believe it was working out to be 1/250, f2.8, iso 400 - 800) The flash is set to ETTL +2. I am usually shooting with a 200 mm 2.8 prime lens.

I am finding a lot of variation in the results, but specifically, close subjects are well over-exposed, more distant (50 yards or so) are well under-exposed. It almost seems like I am getting a consistent burst of light, as if the flash were in manual setting. I have 2 theories-

1. ETTL may not work through the pc connector. Does anyone know if this is the case?

2. I am at the limits of the flash- ETTL +2 is trying to blow everything out, but it only works when the subject is close, and it is just too weak to do anything more for the distant ones.

Since the subjects range from 10-50 yards away when I am shooting, I have steered away from manual flash settings- action happens too quickly to keep guessing at an output based on my guess of the distance.

Anyone have any ideas?

Thanks

Ettl does not work through the pc connector. You need something like the oc-3. I recommed these, cheaper than canon, just as well built and the vendor is a great guy. http://flashzebra.com …rds/ettlcords/i​ndex.shtml

You are getting a manual burst, but even that expecting flash coverage at 50 yards is pretty extreme unless you are maxing out the iso or using a better beemer attachment.

gonzogolf is right. The PC port only sends a "fire" command. Nothing else. TTL requires a 2 way "conversation" if you will. So with only a "fire" your assumption is correct that the flash will go off in a consistent manner as to the settings it is set to. Move closer or farther, it does not matter. The flash will fire the same.

If you wnat to shoot TTL get the cord gonzogolf has suggestted. It should solve the problem to the limits of the flash.

Thanks guys!!

gonzogolf wrote in post #8742560
You are getting a manual burst, but even that expecting flash coverage at 50 yards is pretty extreme unless you are maxing out the iso or using a better beemer attachment.

That brings up a follow-up- It seems to me that I hit kind of a "sweet spot" If I bump up the ISO, then I get more ambient light in the exposure also, which gives me some blurring. Keeping the ISO low limits the range of the flash. As a result, I am using a 200 mm lens, which probably exceeds the reach of the flash a little.

I would love to use a longer lens to get some extra range, but it seems that the flash is about out of range at the 200 mm mark. Any thoughts about increasing the range?

wildlife shooters, and some sports guys use a device called a better beamer (google it) that is a lens device that goes over the front of the flash and focuses the beam so that it projects a bit farther. I've never used one, but some guys really like it.