When raising the brightness of a clip in the timeline of a four minute slide show (widescreen, about 30 images resized to 1000 pixels high x 2000 pixels wide at 72ppi {about a 1.8MB file} in Photoshop Elements 5), it changes the horizontal position in the motion path.
I got around the problem by changing the brightness of the file and saving it under the same name, but why did it change the motion keyframe?