Problem with trailing shutter?

Hi all, I just did a shoot and of the 209 images shot two came out like this. Is this the trailing shutter (or leading shutter?!) These were shot with three Alien Bees (which all fired as far as I am aware. I didn't shoot this immediately after another shot so I think they would have had time to recycle) It, along with the previous shot which came out fine, was shot at f7.1, iso 100, 1/180 sec (on X setting).

Does this look like an intermittent problem with the camera or is there another, less worrying explanation? I have never seen this happen before. I didn't see this on any of the landscape format images which would have proved it was a camera issue (if the black line had been at the bottom).

Shot on my new K5ii with a 16-45 f4 DA.

Thanks for any thoughts you can offer.

Phil

Your Alien Bees are not maintaining X-sync

They are introducing a delay in the signal this delay shifts and occasionally the flash catches the trailing shutter.

Could be a battery issue or even a recovery issue (repeated flash ) but it not camera and unlikely to be  flash issue.

MightyMike wrote:

In my understanding this can happen if a flash is getting over heated, just dropping to 1/160th or 1/125th sec can remedy the issues

Without an external battery pack it difficult to cook a flash, My 540 firing off an ext battery pack can trigger the O/heat protection but it just stops firing and doesn't sync delays.

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Mike from Canada
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