Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 (edited) After the 3/2 pulldown conversion was completed, the final version specs looks like this. Edited August 2, 2016 by Chris Davidson Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 There was a suggestion that the SS recreation video was shot at approx 18/18.3fps. If that was indeed true, the pulldown conversion ratio would have been different. 29.97/18 = 1.665/1 ratio = 5/3 pulldown ratio. Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 (edited) I created a gif showing the end result of reverse telecining which shows the conversion of the 3/2 pulldown or 5 frames back to its original 4 progressive. The top part of the gif is the 3/2 pulldown process from the original. The middle part is the reverse telecine result converting it back to its original four progressive frames. Added on edit: I would suggest downloading this and playing it at full view so the pulldown frames are quite obvious to see. https://drive.google.com/file/d/0BwrExtVD005OTjgyVDJSTXlnZUE/view?usp=sharing Edited August 2, 2016 by Chris Davidson Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 The version of the SS recreation film which includes the pulldown footage is here: Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 It seemed a stretch to believe that Underwood or an associate would have filmed the SS recreation at 18fps since the camera he normally used was most likely a "Bell and Howell Filmo" standard 16mm/24fps camera. The pulldown frames conversion answered that question. Reconstruction shot at 24fps. Link to comment Share on other sites More sharing options...
David G. Healy Posted August 2, 2016 Share Posted August 2, 2016 (edited) There was a suggestion that the SS recreation video was shot at approx 18/18.3fps. If that was indeed true, the pulldown conversion ratio would have been different. 29.97/18 = 1.665/1 ratio = 5/3 pulldown ratio. for those uninitiated, the why's of 29.97fps is explained here... https://documentation.apple.com/en/finalcutpro/usermanual/index.html#chapter=D%26section=6%26tasks=true Edited August 2, 2016 by David G. Healy Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 I then took the liberty of removing all but the progressive frames from the SS reconstruction video so now we're only dealing with whole frames. You might remember this: https://drive.google.com/file/d/0BwrExtVD005OUmxsRlJLSGhwNE0/view?usp=sharing Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 There was a suggestion that the SS recreation video was shot at approx 18/18.3fps. If that was indeed true, the pulldown conversion ratio would have been different. 29.97/18 = 1.665/1 ratio = 5/3 pulldown ratio. for those uninitiated, the why's of 29.97fps is explained here... https://documentation.apple.com/en/finalcutpro/usermanual/index.html#chapter=D%26section=6%26tasks=true There was a suggestion that the SS recreation video was shot at approx 18/18.3fps. If that was indeed true, the pulldown conversion ratio would have been different. 29.97/18 = 1.665/1 ratio = 5/3 pulldown ratio. for those uninitiated, the why's of 29.97fps is explained here... https://documentation.apple.com/en/finalcutpro/usermanual/index.html#chapter=D%26section=6%26tasks=true David, More math, you know how much I hate that subject. Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 I then took the liberty of removing all but the progressive frames from the SS reconstruction video so now we're only dealing with whole frames. You might remember this: https://drive.google.com/file/d/0BwrExtVD005OUmxsRlJLSGhwNE0/view?usp=sharing Now, all one has to do is apply a rate x time = distance equation and/or a frame count comparison between the two films using common Dealy Plaza landmarks in relation to the same part of the vehicles. Here's a hint at this time. That is a 1959 Chevy Impala Sport Coupe. It is 210.9" long = 17.57ft. The difference in length between the two vehicles is 3.77ft Link to comment Share on other sites More sharing options...
David G. Healy Posted August 2, 2016 Share Posted August 2, 2016 There was a suggestion that the SS recreation video was shot at approx 18/18.3fps. If that was indeed true, the pulldown conversion ratio would have been different. 29.97/18 = 1.665/1 ratio = 5/3 pulldown ratio. for those uninitiated, the why's of 29.97fps is explained here... https://documentation.apple.com/en/finalcutpro/usermanual/index.html#chapter=D%26section=6%26tasks=true There was a suggestion that the SS recreation video was shot at approx 18/18.3fps. If that was indeed true, the pulldown conversion ratio would have been different. 29.97/18 = 1.665/1 ratio = 5/3 pulldown ratio. for those uninitiated, the why's of 29.97fps is explained here... https://documentation.apple.com/en/finalcutpro/usermanual/index.html#chapter=D%26section=6%26tasks=true David, More math, you know how much I hate that subject. lol.... simply b&w to color concerns, Chris. Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 (edited) Since I have the landmark frame comparison completed and ready to post, I'll do the R X T = D formula first. I chose z173- z232 for a total of 59 frames partly because we can get feedback on the WC specs from CE884 final plat version of May 1964. Their span from z171-z231= 60 frames @ 63.4ft traveled A 24fps movie using these numbers will get you this: 60/24 = 2.5seconds 63.4ft/2.5sec = 25.36ft per sec = 17.25mph 59 frames using that average would equal the same 17.25mph That would be quite a consistent speed with the overlay comparison movie between the lexus and limo. Added on edit below: Edited August 2, 2016 by Chris Davidson Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 The distance per frame for the 17.25mph average is: 17.25 x 1.47 = 25.35ft per sec / 24 frames = 1.056 ft per frame The 1959 Impala is 3.77ft shorter than the limo so any comparison between the two in terms of landmarks has to be considered. 3.77ft / 1.056ft per frame = 3.57 frames or 4 whole frames added. Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 2, 2016 Author Share Posted August 2, 2016 Before I post the landmark frame comparison, here's my question to non-alterationist believers: If two vehicles travel the same distance in the same amount of film frames, is the frame rate in both cameras the same? I'll give them a little while to ponder that. Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 3, 2016 Author Share Posted August 3, 2016 Link to comment Share on other sites More sharing options...
Chris Davidson Posted August 4, 2016 Author Share Posted August 4, 2016 z173-z232 = 59frames Reconstruction = frame 181-236 = 55 frames 59 Impala is 3.77ft shorter than the limo. 3.77ft made up in terms of average speed throughout this span = 3.57 frames = 4 whole frames. 55 + 4 =59 fames = Reconstruction total The cars front and rear ends in relation to the Stemmons sign are the markers. 59frames to cover the same distance in each film. 59/24fps = 2.458sec 62.35ft / 2.458 = 25.36 ft per sec = 17.25mph The recreation film is shot at 24fps. The extant zfilm is a stepped down frame version. Link to comment Share on other sites More sharing options...
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