Black image with ys-3d duo and canon 550d in TTL mode

[Marouane chems maarif]

Hi,

I have two YS-D3 DUO strobes that I’m using with my Canon 550D. When I use TTL mode on the flashes with a shutter speed of 1/200s, the pictures turn out completely black. Lowering the shutter speed to 1/125s causes the upper third of the image to be overexposed, while the rest remains pitch black. At 1/80s, the picture looks properly exposed. However, when I switch to manual mode with a shutter speed of 1/200s, the pictures are correctly exposed (after manually adjusting the flash power).

The two strobes are less than a week old.

Any suggestions on what could be causing this issue?

 

[JohnnyQuest]

My guess is that your camera is emitting a pre-flash, and your strobe is firing with the timing of the pre flash. With your slower shutter speeds, the lens remains open long enough to catch the “tail end” of the strobe light. But with your higher speed, timing has to be exact. Check to see if you have red-eye reduction on or off. Should be off. Also check to make sure you have the AF auxiliary light turned off.

 

[Marouane chems maarif]

I found the solution. It´s RTFM (read the ******* manual )
The ys-3d duo communicate with different brands of cameras. and for every brand there is a kind of "protocol" that the user has to change in order to get the strobe to work in ttl. For me it was 160. The procedure is discribed under custom settings. i had to find my brand and model and than the settings to apply. Works like a charm now