Oswald in the doorway: the blog of the Oswald Innocence Campaign, by Ralph Cinque

On Wikipedia and elsewhere, it says that Marie Muchmore took the first part of her film at the corner of Houston and Main where she was on the northwest sidewalk. If you think of an intersection as having four corners, she was on the northwest corner. 

Think about where that is in relation to where the limo was when the fatal head shot occurred. It was southeast of it. 

So after she was finished shooting in that direction, she "walked several yards northwestward" according to Wikipedia to film the motorcade as it went down Elm Street.

There's a long narrow reflecting pool there, so I figure she walked to the other side of the reflecting pool. There's a wall separating it from the grassy area, but I don't figure she climbed over the wall. For one thing, that would involve a lot more than "a few yards." For two, there wasn't enough time. And for three, it would have been a pretty tomboyish thing for her to do. 

Here is how an animator depicted her position at the time she was shooting the Elm Street portion.

 So, I figure she was at the wall but not over the wall. 

I've drawn my own diagram of it. 

So, Marie1 is where she was when she was shooting towards Houston Street as the motorcade was entering Dealey Plaza from Main Street. And Marie2 indicates where she was when she filmed the Elm Street portion. Granted, this is very basic and crude. 

But, it shows that at the time Babushka Lady (BL) was shooting, she was on a southeast diagonal to the limo which had already passed her. Mary Moorman at that time appears to have been facing the limo directly, where her line of sight was at a right angle to the limo. And Marie Muchmore, like Babushka Lady, was shooting on a southeast diagonal to the limo, but her diagonal was a little less than Babushka Lady's. 

And that works out perfectly for this to be true:

I don't see any way it could be Mary Moorman's photo. I can't think of any reason why Mary Moorman would have been standing there, waiting for Kennedy to reach her, prepared to take a picture, and the limo was moving VERY slowly, then even though she was poised and ready to click, she waited until he passed her and then photographed him from behind, catching the back of his head.

I can't accept that as a behavior. I can't, and I won't.  

In Marie Muchmore's case, it was a film, not a photo, so she needs no explanation. And in Babushka Lady's case, there was a big man in front of her, so she had to wait until the limo got by him before she had the visibility to shoot. So she has an excuse for shooting the back of JFK's head. Mary Moorman doesn't. 

You can see Mary Moorman on the left. If she had clicked then, she obviously would have captured a very different picture. The motorcycle cops hadn't even reached her yet, and they were in the Moorman photo.  So, those cops had to get past her slightly before she could shoot. So, the limo had to cover some ground, and the motorcycle cops had to cover some ground before Mary could shoot. But, JFK and Jackie were already in the position in which they were captured in the Moorman photo. Do you think they stayed frozen in that position until Mary was ready to shoot? It was a fluid, dynamic, mobile situation. What happened after this is that JFK went slamming back and to the left, and Jackie, purely by reflex, ducked forward and down to get out of the way. But then she came back to him, and then right away she began her trek across the back of the car only to meet Clint Hill. So, the arrangement we see here doesn't happen again. It was a fleeting moment in time. And it was not a moment that Mary Moorman captured on film. These other two women did: Babushka Lady and Marie Muchmore. I am increasingly convinced of it. I do not think Mary Moorman took the Moorman photo.