From: "Byron Nash" Received: from mail-qk1-f175.google.com ([209.85.222.175] verified) by media-motion.tv (CommuniGate Pro SMTP 6.1.0) with ESMTPS id 7189620 for AE-List@media-motion.tv; Mon, 12 Nov 2018 19:44:00 +0100 Received: by mail-qk1-f175.google.com with SMTP id n12so15187227qkh.11 for ; Mon, 12 Nov 2018 10:56:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=heerzEdgeQzupZqmZhGOgbwmN/MazwFvYmRNcA9bd54=; b=tO3Uy4eRPJR5lnYdHPYqHxTvLTCrPqFlUrAthTT1G8nVJ7teu+GML7xutsjGld2LLi eCd41x/FeBgcPPiC79BmOtGnAoMML/hhtUUBM/0oZhC9D3XSuRo2KGqVNIE/RFnhLAua xNhvfszvmnU3Q3LH4Y+JpHtHg5y8YeEhJZkA1o479s55iq1Q6zFNwpn/LTDYyiJqOdtX qlbFR0KLkzUwr11RiTskKxVJNUiOI7svB+YWLluQaKW1bkuNmwWFznCwCR8De+saVjcn 2MQ9ri7aYYnQN3zc+fYBkEtDWaVhinKnYTtRppgMC8AcHmHjliD47UDg/hOLZeFoEUM5 2+FQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=heerzEdgeQzupZqmZhGOgbwmN/MazwFvYmRNcA9bd54=; b=hBhCszbLojEwtRInj/W7fhOoqZEOynfy5k+et1GdwiBTRvFEmZ7ulF1UTQ1Q2SaNJs 6p/c9yP4DgkNO+gm3L56d+JgB4mXSvRl9s4viLSt8t1u3akBEqS7ctq/hQd34OsyyTFW l5wes53Fu6RGy7fJjPcUFzoI7tm+YXfSXvXqtqQAO098MBqTC4I3Nj4E3Uj1PW4rx3Dl X+50X1OL5ava7iBfLHPoAjEt91e38bB59/z4vNLcnrdin4ywG8cNZ6FuiwAyGsalCv1s oDrP7GfhhIvpg9EpLaw3Ea1E1ok0kdj2Va72QgQ0G/L9iPeAdwe0vAhlu+sMA6aBI5zc vxOw== X-Gm-Message-State: AGRZ1gLL1Qgx01Snf5405uQuCthASxSMv4ULLgA54Z886TfSzCfls9kh q3UfWwJ7poXiFS6ALdWNaTF9rqOaLsuDXHLSGPJqbw== X-Google-Smtp-Source: AJdET5cJyNEBfm0M8zv3beyQ4+yKQIsym4bKGQdg8XOviZhhikiFKkvMJMCedzEkwvKX6t7kiedUswshw8q8haCcDD8= X-Received: by 2002:a0c:c993:: with SMTP id b19mr2078217qvk.126.1542049001354; Mon, 12 Nov 2018 10:56:41 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: Date: Mon, 12 Nov 2018 13:56:30 -0500 Message-ID: Subject: Re: [AE] smoothing out 24p To: After Effects Mail List Content-Type: multipart/alternative; boundary="000000000000f3bc05057a7c42e9" --000000000000f3bc05057a7c42e9 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Forgive my terminology. I wasn't referring to the artifact from panning too fast. But the repeated 5th frame when dropping a 24(23.976) clip into a 30(29.97) comp. Sounds like Twixtor is a must. I had a hard time getting AE to give me an interpolated frame since I wasn't retiming it. On Fri, Nov 9, 2018 at 3:00 PM Jim Curtis wrote: > Strobing in film cameras is also tied to shutter angle, which has an > analog in After Effects. Most film cameras have a fixed shutter angle, > which ties the exposure to 1/48 second at 24 FPS, although some cameras > like the Eclair NPR have a shutter you can vary to shorten the exposure > time to 1/96, 1/128 etc. Mr. Peabody would tell us that the physics of > this determines that strobing is more pronounced with shorter shutter > speeds. The visual effect of strobing happens when there=E2=80=99s not s= ome > overlap of image content in consecutive frames. > > This explains it better than I just did: > > https://en.wikipedia.org/wiki/Rotary_disc_shutter > > > > > On Nov 9, 2018, at 1:14 PM, Rick Gerard wrote: > > Critical pan spends are not limited to video cameras. They are determined > by frame rate and motion. Angle of view has something to do with it also.= I > don=E2=80=99t have time to grab my ASC Manual but here is what I think is= an > accurate copy of the charts. > http://frontside.de/dls/pan.htm > > It=E2=80=99s important to remember that the focal lengths given in the ch= arts are > for normal 4 perf pull down 35 mm cameras so the speed/focal length > recommendations would work with a video camera with an APS-C sensor becau= se > it=E2=80=99s about the same size as a classic 35mm film camera. > > Rolling shutter, interlacing, and other factors also gang up on video > cameras shooting at 24/25 or lower. The only perfect solution is to follo= w > the rules. > > On Nov 9, 2018, at 10:47 AM, Warren Heaton > wrote: > > I=E2=80=99ve always considered strobing to be what happens in camera (usu= ally an > early HD camera during a pan rather than a film camera) and judder to be > what happens when animating in After Effects. Now that they=E2=80=99re s= o easy to > use interchangeably, maybe we need a new term like =E2=80=9Cstrudding=E2= =80=9D? (I hope > some else is laughing at that like I am.) > > > > -Warren > > > > > On Nov 9, 2018, at 10:15 AM, Jim Curtis wrote: > > I=E2=80=99m old and I don=E2=80=99t like the new term for what I was taug= ht in film school > is =E2=80=9Cstrobing.=E2=80=9D I never heard of =E2=80=9Cjudder=E2=80=9D= until film started being > transferred to tape and then the tape was posted on tape. > > And we hated it! > > :) > > > > On Nov 9, 2018, at 10:37 AM, Rick Gerard wrote: > > There is a thing called critical pan speed. The combination of movement, > frame rate and retinal retention mean that any movement in the frame that > falls in the range of critical speeds will judder. The way to reduce the > problem is to shoot at higher frame rates. Unfortunately, higher frame > rates mean less motion blur and we like to have motion blur so the footag= e > looks more like a movie and less like a video. > > If you are stuck with problematic footage that was shot at 24 (or any > frame rate) you have two options. Change the timing of the shot, which ma= y > result in audio problems or unnatural action, or force some motion blur o= r > use some software to generate extra frames to try and hide the problem. A= ll > you have to do to change the timing is change the interpretation of the > footage (File>Interpret Footage>Main). Forcing motion blur can be done wi= th > CC Force Motion blur, but really good =E2=80=9Cnew=E2=80=9D frames can re= ally only be > generated with 3rd party software. > > Twixtor is really good at interpolating extra frames. If you want more > frames and you want the timing to stay the same then you have to increase > the frame rate of the comp (sequence in Premiere Pro) and use something > like Twixtor. Force Motion Blur will work when the frame rate for the > footage and the comp are the same, but the results are not as good. > > I hope this makes sense to you. The ASC handbook has had critical panning > speed tables in it for a zillion years. If you don=E2=80=99t pay attentio= n and > check on the set it=E2=80=99s pretty easy to end up with shots that can= =E2=80=99t really be > fixed in a pleasing way. > > Here are a couple of articles from the After Effects FAQ section of the > Adobe Forum on avoiding and overcoming the problem: > "Avoiding judder in motion graphics" by Rick Gerard > > "Best practices for creating text and vector graphics for video=E2=80=9D > > > I hope this helps. > > On Nov 9, 2018, at 7:42 AM, David Baud wrote: > > Following are I think your options: > If you are dealing with unsync clip (no sound matching critical), you > could interpret your footage to play at 23.976fps, and they will play a > little faster at 29.97fps (duration will be shorter). > If you are editing with interlaced footage (kind of unusual these days > other than for broadcast masters), then you could add pulldown during you= r > AE export. > Otherwise you will have to recreate these missing frames one way or > another=E2=80=A6 using a plugin like Twixtor... > > David Baud > Colorist & Finishing Editor > david at kosmos-productions.com > > On Nov 9, 2018, at 7:12 , Byron Nash wrote: > > I'm drawing a blank here. Tried a few solutions and haven't gotten the > solution yet. I have some 23.976 footage that I'm using in a 29.97 > sequence. I'd like to use optical flow to eliminate that judder frame tha= t > is present when putting 24p footage into 30p timelines. What's the way to > get this done? I feel like I've done it before. Checking the frame blendi= ng > box doesn't seem to fix it. I'm not changing the speed of the clip. > > Thanks > > > > > > > > --000000000000f3bc05057a7c42e9 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Forgive my terminology. I wasn't referring to the arti= fact from panning too fast. But the repeated 5th frame when dropping a 24(2= 3.976) clip into a 30(29.97) comp. Sounds like Twixtor is a must. I had a h= ard time getting AE to give me an interpolated frame since I wasn't ret= iming it.=C2=A0

On Fri= , Nov 9, 2018 at 3:00 PM Jim Curtis <AE-List@media-motion.tv> wrote:
Strobing in film cameras is also tied to shutter angle, which has an an= alog in After Effects.=C2=A0 Most film cameras have a fixed shutter angle, = which ties the exposure to 1/48 second at 24 FPS, although some cameras lik= e the Eclair NPR have a shutter you can vary to shorten the exposure time t= o 1/96, 1/128 etc.=C2=A0 Mr. Peabody would tell us that the physics of this= determines that strobing is more pronounced with shorter shutter speeds.= =C2=A0 The visual effect of strobing happens when there=E2=80=99s not some = overlap of image content in consecutive frames.

This exp= lains it better than I just did:




On Nov 9, 2018, at = 1:14 PM, Rick Gerard <AE-List@media-motion.tv> wrote:

Critical pan spends are not limited to= video cameras. They are determined by frame rate and motion. Angle of view= has something to do with it also. I don=E2=80=99t have time to grab my ASC= Manual but here is what I think is an accurate copy of the charts.

It=E2=80=99s important to reme= mber that the focal lengths given in the charts are for normal 4 perf pull = down 35 mm cameras so the speed/focal length recommendations would work wit= h a video camera with an APS-C sensor because it=E2=80=99s about the same s= ize as a classic 35mm film camera.

Rolling shutter, = interlacing, and other factors also gang up on video cameras shooting at 24= /25 or lower. The only perfect solution is to follow the rules.
On Nov 9, 2018, at 10:47 AM, Warren Heaton = <AE-List@me= dia-motion.tv> wrote:

I=E2=80= =99ve always considered strobing to be what happens in camera (usually an e= arly HD camera during a pan rather than a film camera) and judder to be wha= t happens when animating in After Effects.=C2=A0 Now that they=E2=80=99re s= o easy to use interchangeably, maybe we need a new term like =E2=80=9Cstrud= ding=E2=80=9D? =C2=A0(I hope some else is laughing at that like I am.)



-Warren




O= n Nov 9, 2018, at 10:15 AM, Jim Curtis <AE-List@media-motion.tv> wrote:
I=E2=80=99m old and = I don=E2=80=99t like the new term for what I was taught in film school is = =E2=80=9Cstrobing.=E2=80=9D =C2=A0I never heard of =E2=80=9Cjudder=E2=80=9D= until film started being transferred to tape and then the tape was posted = on tape. =C2=A0

And we hated it!

:)



O= n Nov 9, 2018, at 10:37 AM, Rick Gerard <AE-List@media-motion.tv> wrote:
<= br class=3D"m_7970764974776516838Apple-interchange-newline">
There is a thing cal= led critical pan speed. The combination of movement, frame rate and retinal= retention mean that any movement in the frame that falls in the range of c= ritical speeds will judder. The way to reduce the problem is to shoot at hi= gher frame rates. Unfortunately, higher frame rates mean less motion blur a= nd we like to have motion blur so the footage looks more like a movie and l= ess like a video.=C2=A0

If you are stuck with problemati= c footage that was shot at 24 (or any frame rate) you have two options. Cha= nge the timing of the shot, which may result in audio problems or unnatural= action, or force some motion blur or use some software to generate extra f= rames to try and hide the problem. All you have to do to change the timing = is change the interpretation of the footage (File>Interpret Footage>M= ain). Forcing motion blur can be done with CC Force Motion blur, but really= good =E2=80=9Cnew=E2=80=9D frames can really only be generated with 3rd pa= rty software.

Twixtor is really good at interpolat= ing extra frames. If you want more frames and you want the timing to stay t= he same then you have to increase the frame rate of the comp (sequence in P= remiere Pro) and use something like Twixtor. Force Motion Blur will work wh= en the frame rate for the footage and the comp are the same, but the result= s are not as good.

I hope this makes sense to you.= The ASC handbook has had critical panning speed tables in it for a zillion= years. If you don=E2=80=99t pay attention and check on the set it=E2=80=99= s pretty easy to end up with shots that can=E2=80=99t really be fixed in a = pleasing way.=C2=A0

Here are a couple of articles = from the After Effects FAQ section of the Adobe Forum on avoiding and overc= oming the problem:

I hope this helps.

On Nov 9, = 2018, at 7:42 AM, David Baud <AE-List@media-motion.tv> wrote:

Following are I think your options:
If you are dea= ling with unsync clip (no sound matching critical), you could interpret you= r footage to play at 23.976fps, and they will play a little faster at 29.97= fps (duration will be shorter).
If you are editing with interlaced foot= age (kind of unusual these days other than for broadcast masters), then you= could add pulldown during your AE export.
Otherwise you will hav= e to recreate these missing frames one way or another=E2=80=A6 using a plug= in like Twixtor...

David Baud
Colorist & Finishing Editor
david at kosmos-productions.com

On Nov 9, 2018, at 7:12 , Byron Nas= h <AE-List@= media-motion.tv> wrote:

I'm drawing a blank here. T= ried a few solutions and haven't gotten the solution yet. I have some 2= 3.976 footage that I'm using in a 29.97 sequence. I'd like to use o= ptical flow to eliminate that judder frame that is present when putting 24p= footage into 30p timelines. What's the way to get this done? I feel li= ke I've done it before. Checking the frame blending box doesn't see= m to fix it. I'm not changing the speed of the clip.

Thanks




<= /div>
--000000000000f3bc05057a7c42e9--