Swan-Song -- Math Rules

[Chris Davidson]

Referring back to post134 and CE884 data, if you move past the z168-z171 entries where the car is traveling at 3.74mph, and deal with the next span of frames, in this case z171-z186 where Myers z171-z175 would intersect.

15frames @ 20.7ft traveled

18.3 frames/15frames = 1.22 x 20.7ft = 25.254ft per sec / 1.47(1mph) = 17.18mph

[Chris Davidson]

The difference being:

17.18mph - 11.2 mph = 5.98 mph

5.98mph x 1.47(1mph) = 8.79ft

Connection Completed.

[Chris Davidson]

The speed of the limo from z154-z166 is (23.05ft per sec) 15.68mph.

In 5 more frames up to z171, I will make the assumption it is traveling the same speed.

So, z154-z171= 15.68mph.

CE884 the orange version, z171-z185 = 17.18mph

CE884 the orange version, z185-z186 = 18.673 mph

The above speeds of the extant zfilm would appear to be more representative of what we see at this point in time.

chris

If interested, you can now start tying the previous post all the way back to this, which was post #12.

[Chris Davidson]

The equation broken down for those who don't want to do the conversion:

15.116ft- Distance from limo front to JFK in limo

divide

12 - Total frames from 154-166

=1.259666…. ft per frame

x

18.3 - Frames per sec

= 23.05ft traveled in 1 second @ 18.3 frames per sec

divide

48 frames per sec true camera speed at this point

= .48 ft per frame

x 5 frames (z161-166)

= 2.4ft = distance between JFK and Connally in limo.

= 5 true consecutive frames from a 48fps film.

Added on edit: I use 1.47ft per sec (rounded off from 1.466) as my multiplier for mph conversions.

chris

Analogous to the above, converting the missing 8.79ft

8.79ft / 18.3frames per sec = .48ft per frame = match, in terms of ft. per frame, to a limo traveling 23.05ft (15.68mph) @ 48frames per sec.

[Chris Davidson]

Or, in terms of a 48/18.3 fps ratio conversion:

48/18.3 = 2.622

2.622 x 7frames(CE884 z161-z168 same station#) = 18.3 frames in a 48fps version or one second in a 18.3 fps version.

And,

2.622 x 5.98mph(8.79ft per sec) = 15.68mph - see previous post for relevance.

Edited June 6, 2016 by Chris Davidson

[Chris Davidson]

The equation broken down for those who don't want to do the conversion:

15.116ft- Distance from limo front to JFK in limo

divide

12 - Total frames from 154-166

=1.259666…. ft per frame

x

18.3 - Frames per sec

= 23.05ft traveled in 1 second @ 18.3 frames per sec

divide

48 frames per sec true camera speed at this point

= .48 ft per frame

x 5 frames (z161-166)

= 2.4ft = distance between JFK and Connally in limo.

= 5 true consecutive frames from a 48fps film.

Added on edit: I use 1.47ft per sec (rounded off from 1.466) as my multiplier for mph conversions.

chris

Analogous to the above, converting the missing 8.79ft

8.79ft / 18.3frames per sec = .48ft per frame = match, in terms of ft. per frame, to a limo traveling 23.05ft (15.68mph) @ 48frames per sec.

And, if you take that 8.79ft distance over 48frames = 8.79/48 = .183ft per frame.

You can then look at the published WC CE884 document for z161-z166 a five frame span with distance traveled of .9ft =

.9ft / 5frames = .18ft per frame

Pretty conclusive. imo

[Chris Davidson]

Here it is as an equation:

.48ft per frame = 48frames per sec scenario, limo traveling at 15.68mph

-

.18ft per frame = B.S. speed of limo @ CE884 z161-z166

= .30ft per frame = B.S. speed of limo @ CE884 z168-z171 final WC plat of May 1964

= Jackpot

Edited June 7, 2016 by Chris Davidson

[Chris Davidson]

Link the 7 frame difference (z161-z168 same station# both CE884's) in a 48fps scenario, starting at post#40:

48frames -7 frames = 41 frames.

15.68mph = 15.68 x 1.47 / 48 = .4802ft per frame

41frames x .4802ft per frame = 19.69ft traveled, approx (less than 1 inch) = 19.756ft

Added on edit: 19.756 ft per sec = 13.44mph

Edited June 7, 2016 by Chris Davidson

[David Josephs]

Wow Chris... Well done. The easiest way to create an end product at 18.3fps is to cut down from 48fps, not try to add frames from 16fps. That the incline of Elm is exactly the same 18.3:1 ratio as the film speed per frame makes the math coordination much easier.

To create the illusion of constant speed - while testimony claims they almost stopped at the turn and most definitely slowed to a crawl around extant frame 300 one only need to watch the QT movie of the stable version BACKWARD which QT allows you to do easily. We can even see the limo speeding up as it moves backward towards Houston prior to z313. the Limo most definitely does not travel at a constant speed, yet somehow it is made to look as if it does... Cutting the right frames in the correct amount from 48fps will produce what we see.

Can you please relate the slow wide turn onto Elm which Truly describes and the speeds we see here... or does it provide no effect since it occurs prior to 133? I simply do not understand how that wide turn is hidden within Towner?...

Mr. TRULY. That is right.
And the President's car following close behind came along at an average speed of 10 or 15 miles an hour. It wasn't that much, because they were getting ready to turn. And the driver of the Presidential car swung out too far to the right, and he came almost within an inch of running into this little abutment here, between Elm and the Parkway. And he slowed down perceptibly and pulled back to the left to get over into the middle lane of the parkway. Not being familiar with the street, he came too far out this way when he made his turn.
Mr. BELIN. He came too far to the north before he made his curve, and as he curved--as he made his left turn from Houston onto the street leading to the expressway, he almost hit this north curb?
Mr. TRULY. That is right. Just before he got to it, he had to almost stop, to pull over to the left. If he had maintained his speed, he would probably have hit this little section here.
Mr. BELIN. All right.

Bell doesn't have it and neither does Towner... how dat Chris?

[Chris Davidson]

I've said in the past, throw out the B.S. limo speed of CE884 z161-z166 (18.3fps scenario) = 2.24mph.

Then, take the correct speed of 15.68 mph (48fps scenario) and subtract the B.S. speed:

15.68mph - 2.24mph = 13.44mph = match for previous post.

Conversion Completed.

[Chris Davidson]

Can you please relate the slow wide turn onto Elm which Truly describes and the speeds we see here... or does it provide no effect since it occurs prior to 133? I simply do not understand how that wide turn is hidden within Towner?...

David,

I do not have an answer for this.

It would seem unlikely that Truly would go into so much detail about this occurrence, unless it was a way to accommodate more time synchronization needed, traveling further down Elm St.

Is there anybody else that backs up Truly with similar testimony about the wide turn?

Here is Towner (background stabilized) along with her filming position in relationship to the existing layout.

[Chris Davidson]

Let me hypothesize that Position A is the beginning of a frame count sequence.

In this case, one that consists of a film shooting at 48fps.

The span from Position A to z168 = 168 frames.

168/48fps = 3.5 seconds.

David,

I don't want to get sidetracked too much with Towner right now, but I'll do a little math for you, and if you want to expand on Towner, just start another topic, which I would be willing to contribute to.

Since Position A crosses paths with Towner's film span, this might be of relevance:

In order to sync films, Myers puts Towners camera fps speed at 22.8.

Towners camera is a Sears Tower Varizoom 8mm. It is either going to shoot normally at 16 or 18fps if its a later model. Lets give it the benefit of the doubt and say it shoots at 18.3fps.

The difference between Myers fps sync speed and a normal Towner fps rate is 22.8 - 18.3 = 4.5fps

If the span from Position A to z168 (initial entry on WC plat CE884) is 168frames/48fps = 3.5seconds, then

4.5fps difference x 3.5 sec = 15.75 frame difference @18.3fps.

If you take a look at the excerpt from Myers, at the bottom, he states there is a gap between Z starting and Towner ending. The gap is .82 sec.

.82 x 18.3 fps = 15.006 frames

I'm starting to get the distinct feeling that Towner's film might have been shot at 48fps or parts thereof, hence the silly frame rate Myers was forced to use, to sync Towner.

It was my understanding that Jim Towner handed Tina the camera and told her to start shooting, if somebody didn't know any better, they more than likely would press down hard and floor the film lever, which is exactly where the Slow-Motion mode resides. Speculation, but it makes a lot of sense. Especially with the story about the Towner splice and Life Magazine.

P.S. Total extant Towner frames, including 7 missing, according to Myers = 167

Edited June 8, 2016 by Chris Davidson

[Chris Davidson]

And,

To finish it, in terms of 48fps:

48/18.3 = 2.622/1

15.75 frames x 2.622 = 41.3frames =

Mr. SHANEYFELT. Yes; we have established that the Zapruder motion picture camera operates at an average speed of 18.3 frames per second. And we have been advised that the minimum time for firing the rifle in successive shots is approximately two and a quarter seconds. So this gives us then a figure of two and a quarter seconds of frames; at 18.3, this gives us this figure of 41 to 42 frames.

Representative FORD. Would you repeat that again, please?
Mr. SHANEYFELT. The camera operates at a speed of 18.3 frames per second. So that in two and a quarter seconds it would run through about 42--41 to 42 frames.

Edited June 9, 2016 by Chris Davidson

[Chris Davidson]

Myers average speed from z150-175 = 10.5mph

Myers average speed from Towner end to z175 = 9.8mph

10.5 x 2 = 21- 9.8 = 11.2mph = speed traversed from z150-z175

In case you had forgotten, excerpt from post #84:

Looking at CE560, a few remarks are in order.

To figure out the exact(vehicle/bullet) speed Frazier uses, note the line starting with: Ave Vel= Average Velocity

Ave Vel = 175/2070 = .085 sec

1sec/.085 = 11.764…. x 1.4ft = 16.47ft per sec =11.2mph

Or, this way: .085/.0546(1frame/18.3fps) = 1.556frames 1.4ft per 1.556frames = .8997...ft per frame x 18.3fps = 16.465ft per sec/1.47(1mph) = 11.2mph

Mr. SHANEYFELT. Yes; because we were able to determine the speed of the camera, and thereby accurately determine the length of time it takes for a specific number of frames to run through the camera at this 18.3 frames per second, and having located these frame positions in the street, we took the farthest distance point we had in the Zapruder film which was frame 161 through frame 313.

This was found to run elapsed time from the film standpoint which runs at 18.3 frames a second, runs for a total of 8.3 seconds.

This distance is 136.1 feet, and this can be calculated then to 11.2 miles per hour.

[Chris Bennett]

Chris, I'm sure you've mentioned this in an earlier post somewhere. But is it your opinion that Zapruder shot in slow motion (48 FB's) and that that film was altered at Hawkeye Works to bring it down to 18.3 fps?

Do you also feel that they made splices in the film such as the turn? And that they cropped the field of view at the bottom? Just wanted to make sure I knew where you (and perhaps David as well) stood on the film.

I seemed to remember a photo of you standing in the place Zaprider was. Did you take some test film of your own?

Recently I obtained one of the B&H Directors cameras and some film, and was interested in doing some tests as well.

-Chris