shutter problem

[arcanej]

Today, every picture I took with my 5DIII has a black bar on the bottom of the frame, regardless of the lens I used. The camera has not suffered any recent impact (of which I am aware). Is this indicative of some problem with the electronic shutter? I assume I will have to send this into a Canon repair shop to get this fixed.

 

[Loswr]

Sounds like a problem with the mechanical (not electronic) shutter, call Canon.

Unless all the shots are with flash, in which case it may be a sync speed issue.

 

[arcanej]

I was shooting with flash (Einsteins controlled with the Cyber Commander). I just took a picture of a white wall with the flash off and it seems like it may be a flash sync problem.... How do I resolve this? Once again, thank you for your help and insight.

 

[Loswr]

Assuming you're shooting at 1/200 s, use a slower shutter speed - 1/160 s or 1/125 s.

 

[arcanej]

I'll try that. I was shooting a dancer so I set it to 1/250th a second to freeze motion. I've used identical settings dozen times before without a problem. I did, however, buy a third Einstein strobe and this is the first time I've used all three in unison.

 

[arcanej]

I realize in writing that out I am being stupid.... it's the strobe that freezes the action not the shutter speed. Still, I've never had a problem at this setting before.

 

[Loswr]

1/250 s isn't enough to freeze the motion of my 5 year old when she dances - I doubt your shutter is freezing the dancer. The duration of the flash is much shorter, particularly if you set the Einsteins to action mode instead of constant color temp. In color mode (default for the Einstein) a full power pop is 1/540 s, as you drop power it gets faster (1/1700 s at 1/2-power, ~1/8000 s at min power). Action mode is a little faster.

You just need to make sure the shutter is fully open when the flash fires. At speeds faster than Xsync (1/200 s for the 5DIII), the second curtain starts closing before the first cutrain completes its traverse. Going 1/3-stop slower than Xsync ensures the curtain is fully open with a cushion for trigger timing not being perfect (it rarely is with 3rd party triggers).