Secondary flash not showing up

Hi all
I bought one of the Wein hot shoe flash slave trigger. It is consistently triggering the secondary flash,(SB28) but only occasionally is the second flash in the image. I know it is firing because I am seeing spots from watching this thing fire. Second flash is set to manual. I tried different settings from full to 1/64th.

I have tried slower and faster sync and shutter speeds. I have tried Slow and Rear sync. I have tried diffuser/ no diffuser. I have tried bounce/straight on. Nothing consistenly catches the second flash. I tried repeating the same set up immediately, and gotten no second flash in the image. Even knowing it would make no difference, just for the hell of it I tried different f stops.

Second flash too early or too late?

Got any ideas?

David

 

Hi Ronnie
I tried TTL,AA, A,TTL BL, and manual as well as setting the flash sync to AutoFP. No difference that I could recognize.
David

 

Ronnie,
The slave SB28 was always set to manual. I tried all the variations on the SB800.
But, I did make progress. It seems that these are very sensitive to power levels of the batteries. Newly charged batteries make it function properly. Batteries that still have sufficient power to fire the strobe may not have the juice to run the trigger. Maybe it was triggering late or not at all ????? Weaker batteries also increase the necessity to get the sensor aimed absolutely correctly. As you suggest.
Placed behind a chair and loaded with charged batteries, it will sense the bounce off the wall and fire properly. Weakened batteries make it either not fire or nor fire at the right time.
So, it is working OK, but I'm wondering if a different product might perform a bit better.
Thanks for your input
David