I was taking High Dynamic Range (HDR) photos of Gatineau across the Ottawa River from Nepean Point in Ottawa at 11:45AM on 11 November 2009. I was using a 14mm rectilinear lens on a full-frame camera, mounted vertically. My HDR photos were taken in two bursts of three exposures in close sequence (within one second per burst). The two bursts were 14 seconds apart. Upon close examination of the photos that evening, I noticed a white object in the clear blue sky travelling southwesterly.

 

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