580EX II question

Stupid question, but I often cannot get my Canon 580EX II to fire when I have a softbox attached to it. However, if I use a single finger and gently lift the softbox up a quarter inch, it fires. I am thinking the softbox is blocking something...maybe the AF-assist emitter, or perhaps a sensor, on the flash unit. Can someone explain to me what is going wrong and how I can fix it?

Is the flash on camera, or how are you triggering it?

Do you know that the 580 tilts *down* a tiny bit? (Officially, 7 degrees.) And anytime the flash is not pointing straight ahead (up or that tiny bit down), it affects things like using preflash (or not) and collecting distance info (or not).

The point is that there is a position sensor in the head that includes being down too far. My first thought is to check that the head is firmly in the straight ahead position.

dasmith232 wrote in post #19044360
Is the flash on camera, or how are you triggering it?

Do you know that the 580 tilts *down* a tiny bit? (Officially, 7 degrees.) And anytime the flash is not pointing straight ahead (up or that tiny bit down), it affects things like using preflash (or not) and collecting distance info (or not).

The point is that there is a position sensor in the head that includes being down too far. My first thought is to check that the head is firmly in the straight ahead position.

I believe that when tilted down the flash icon blinks to let you know it is in this position. This is mentioned in the manual, to be found at https://www.usa.canon.​com …lite-580ex-ii?tab=manuals.

Many years ago, there were threads on POTN about the inability of the eTTL to properly meter and command an amount of light from the flash when softboxes are put on the eTTL flash...in spite of the fact that the 580EX can properly bounce flash with eTTL exposure done properly!

I have not repeated eTTL flash with softbox testing, using more current Canon bodies than we had 10-15 years ago.

Need to know: What type of softbox and mount are you using? What type of triggering are you using? If you put the flash, camera and focus in manual mode, is there any difference?

The tilt makes sense, but there is a blinking icon in the -7 degree position so you will know. A softbox will block the AF assist beam regardless, unless it is a very small softbox

There was always a weakness with the foot of the 580EX and EX II, so if the weight of a softbox was on the flash head rather than supported by a bracket, the plastic would break above the foot. The II was much better than the original, but still not designed to bear weight. Check if there is play near the lever lock. If so, you need to remove the foot and disassemble and reassemble it.