7D-Pixel King-YN560 and Dark Area of the Picture

I have been using my pixel kings and 2 YN560's with my 60D for a couple months, I shot 1000+ pictures without a problem. Today I used 7D first time with the same set-up, one every ten pictures has the same problem : there is a dark area at the top of the pictures. (A sample is attached)

If it was on the sides (vertical dark strip) I would say synchronization, but as far as I know curtains are moving side ways, not up and down, right ?
Never had any problems with 7D before, but I am using 7D mostly outdoors without flash. (using more than a year)

I am using Manuel mode, shutter speeds less than 1/200.

Any ideas ?

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Looks like curtain try going lower shutter speed. Bodies can differ,I would try that first

+1 for shutter. Shutters move vertically now. Only the old cloth curtains moved sideways.

Try replacing the batteries in the triggers as well. Dying batteries seem to misfire more often (at least on the RF602's).

If it were too fast a shutterspeed, the curtain would be at the bottom.

Weird. Looks like the flash is firing too soon, but I've no idea what could cause that.

Thanks to everyone for answers. If the curtain moving upside down, there is nothing to worry about, at least it is not a sensor issue. Looks like just a synchronization issue.
I will let everybody know if changing batteries solve the problem.

Could it be some weird wonky rear curtain sync perhaps?

Its a TTL sync timing issue. Either the King is randomly sending a fire signal too soon or maybe the depleted battery consideration is right.

The tech guy at MAC group, Pocketwizard distributor in US, told me not to use rechargeable batteries in my FlexTT5s. They are voltage sensitive and the rechargeable are too close to the threshold, even with freshly charged.

Did you ever figure this out?

The YN560 is known to be not fully compatible with the Kings.

The curtains in most Canon DSLRs move down and up. in this case, the second curtain is descending as it starts to close at the end of the exposure. The YN560 is probably firing too late - perhaps as a result of some mode introducing a delay. The 7D shutters are fast!

The Kings work well with rechargeable 1.2v AAs. They seem to get flakey at less than 1.0v under a 27ohm test load.

dmward wrote in post #13405073
Its a TTL sync timing issue. Either the King is randomly sending a fire signal too soon or maybe the depleted battery consideration is right.

The tech guy at MAC group, Pocketwizard distributor in US, told me not to use rechargeable batteries in my FlexTT5s. They are voltage sensitive and the rechargeable are too close to the threshold, even with freshly charged.

What Dave said is the issue.

The shutter curtain physcially travels from the top to the bottom. So, if the dark band is at the top**, the flash is firing before the 1st curtain has opened completely. If the issue were with the 2nd curtain sync, then the band would be at the bottom as is the case when a higher than max sync speed is used with a flash.

**Note: If this sound counter-intuitive, just remember that the image that's projected on to the image sensor is upside-down so the top of the image is actually at the bottom of the image sensor.

After three years, I started to use my pixel kings and YN560s. I had the similar problem.
I tried several settings like first curtain-manual flash, M-S1-S2 settings on flash. Nothing solved my problem.
Finally, I replaced all the batteries and they started to work again !
Also, settings on the camera are : Manual Flash, Wireless Function disabled, First Curtain (Hi speed also works). Settings on flashes : M
In case someone needs it.