In 323, there is a large, bright area to the lower left of JFK's head.  The sun line is from the upper left to lower right, so this could conceivably be Jackie's dress illuminated by the sun and its boundary on the right a shadow line on Jackie.  Comparison with 328 shows this is not the case.  The line to the left in 328 above is the sun line determined by the man in the background and his shadow.  The line on the right is drawn parallel to that line along the edge of the bright area.  Since the sun is far off the image, this line closely approximates the sun line there.  The bright area is where Jackie's head would be casting a shadow on her body, so there is no reasonable way to interpret the bright area in 328 as being the part of Jackie's body illuminated by sunlight unless her sweater is bulging out a lot.  In addition, JFK has moved forward relative to Jackie between 323 and 328 and the edge of the bright area has moved with him.  The bright area is then part of a large flap hanging well down below JFK's shoulder.  (Arrows point to the edge in the images at the top of the page.) 
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323 328 Sun line in 328
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313 323

Many believe 313 shows matter being blown out of the head to the front.  The matter is completely opaque, however, which suggests it is not all spray.  Also, it seems to hug JFK's face and it narrows away from the head.  This is the opposite shape usually associated with matter being ejected at a bullet exit which tends to expand away from the exit.  In the next frame, the opaque region has been replaced by a smaller region that is otherwise similar in appearance.  Perhaps the area in 314 is the same matter that is seen in 313.  In 313, it is whipping out in front of the head.  It then gets folded or curled up and later unfolds and is seen as the large flap in 323 and 328.  The flap is moving rapidly in 313, so what is seen is not really a snapshot of it but its maximum extent during the exposure.  It  could be slinging off spray and debris. A tracing was made around the flap in 323 and then rotated and placed on 313 showing the bright red area in 313 has about the same size and shape as the flap in 323.  The viewing angle might have changed, however, which would change the relative sizes and shapes.  This is just a rough test.


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313 314
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Click on the thumbnail on the left for an animation is frames 321 to 330. By the end, it is apparent that bright area is not JFK's face but is matter hanging from his head.





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At first glance, it appears that the flap is hinged on the viewer's left at the back of the head in 328, but if the flap were just flipped over to the left, it would be hanging down JFK's back.  The part that we see at the back of the head must actually come from the front so we would have to pull the flap forward after it was flipped over to put it back in place.  Rather than being hinged, the flap must be hanging by a strap.  There is an unfortunate blur after 330 so it is not clear what happens, but JFK's head looks much different in 333 (left).  JFK was falling freely through frame 330 but by that frame, Jackie has her right hand on JFK's head. Her left hand must be on his chest as she has stopped him from falling.  While he was falling, gravity would not make the flap move (much) relative to the rest of the head.  Once he was stopped, the flap would swing to the front a bit.

328 333

 By 333, Jackie has turned JFK's head so that the view is more from the side than in 321-330 where the view is more from the back.  In 333, it is apparent that the flap is attached at the front since it hangs from there.  In 313, the edge of the bright red area that hugs JFK's head is where the flap is attached.