Latest post Sun, Apr 11 2010 5:06 PM by Job ter Burg. 19 replies.
Page 1 of 2 (20 items) 1 2 Next >
Sort Posts: Previous Next
  • Sat, Apr 10 2010 4:55 PM

    • jrp130
    • Not Ranked
    • Joined on Sat, Apr 10 2010
    • Posts 11
    • Points 155

    film 24fps - tk 25fps - sound - ??fps

    this may be a long post so forgive me - i am very confused and this seems to be the place...!

    i usually do 25fps tv commercial work but am now cutting a feature shot on 3perf 35mm @ 24fps. we tk'd to beta sp with the usual 25fps speed up and i set a 24fps pal project with audio transfer at film rate (100%).

    on day 3 the sound guy tells me he's recording sound at 24fps but lot's of people much smarter than i am told me that sound must be recorded at 25fps, the producer says all his film have been done this way too. i then found some equally smart folks who said that sound at 24fps will be fine too. i now have the sound and indeed it imports fine direct from a lacie drive and holds sync for the duration of the clips - i've yet to cut anything of any length really.

    so......

    who's right and why and also how come both camps seem equally certain and both ways seem to work??

    we will end up with HD master for dvd distribution and a digital cinema print for theatres with a possible film out - funds, as ever, permitting. i will output omfi files for the sound dept at this stage. i've also been told to export all picture files - playouts/edls etc @ 25fps and all files for sound dept @ 24fps. this seems weird but again everyone swears it's the golden rule. 

    like...er...how come!?

    forgive my ignorance and thanks in advance 

     

     

    Filed under: , , , , ,
  • Sat, Apr 10 2010 5:15 PM In reply to

    Re: film 24fps - tk 25fps - sound - ??fps

    This may help get your head around this:

    Put simply the confusion will occur when you put the expression f.p.s in any sentence to do with sound.

    It is like saying that you are six pints tall.

    What your recordist is saying that the timecode that he is putting on the sound rushes is arbitrarilly divided into 24 units. He could use 25 fps code  and all would be the same. The seconds counter would count at the same rate.

    Symphony 7.06 OS 10.9.5 QT 7.6.3 Mac Pro 2x2.66 6-core 32GB Ram Aja Kona Lhi. MC 7.0.6 OS 10.9.5 Mac Pro 5.1 2x2.97 6-core 32GB ram Aja I/O express, Apple... [view my complete system specs]
  • Sat, Apr 10 2010 5:25 PM In reply to

    • jrp130
    • Not Ranked
    • Joined on Sat, Apr 10 2010
    • Posts 11
    • Points 155

    Re: film 24fps - tk 25fps - sound - ??fps

     

    hi nubus and thanks for your reply.

    i kind of get what you're saying and i have had people say 1second of sound is 1 second of sound weather it's at 24/25/30fps...it's still one second.

    but then i read things like this;

    Camera 24, TK25 Audio timecode MUST be at 25fps (otherwise the dubbing theatre will get very upset or, if the editor is doing audio sync in Avid, then if the audio timecode is 24fps the Avid will assume the project is NTSC and similarly get very upset). It is possible to gearbox the timecode, but this will introduce lip sync errors and should be avoided. Alternatively the location DAT could be cloned to a 25fps tape and that timecode and audio used for the remainder of the post process, but that introduces additional costs for the production. i forgot to mention i am syncing in the avid using clapper boards not t/code - does this have an impact on your reply? is the net result that it doesn't matter either way then what t/code he stamps the audio with? thanks again.

  • Sat, Apr 10 2010 5:25 PM In reply to

    Re: film 24fps - tk 25fps - sound - ??fps

    Oh, yes and sound post in PAL land like everything to run at true speed- Hence playout at 24fps.

    Picture post likes to have playouts that reference every frame without the 24/25 bunny skips you get on a PAL monitor when running true speed. EDL's and guides playouts should be frame for frame, and playout tapes in PAL format are therefore run 4% fast.

    Symphony 7.06 OS 10.9.5 QT 7.6.3 Mac Pro 2x2.66 6-core 32GB Ram Aja Kona Lhi. MC 7.0.6 OS 10.9.5 Mac Pro 5.1 2x2.97 6-core 32GB ram Aja I/O express, Apple... [view my complete system specs]
  • Sat, Apr 10 2010 5:35 PM In reply to

    Re: film 24fps - tk 25fps - sound - ??fps

    The features I have done have used 25 frame code on the sound rushes, Without knowing exactly how they will bring in material into the sound editor other than your OMF, I cannot see how this should cause any problem. What is the sound recordist recording on?

     

     

    Symphony 7.06 OS 10.9.5 QT 7.6.3 Mac Pro 2x2.66 6-core 32GB Ram Aja Kona Lhi. MC 7.0.6 OS 10.9.5 Mac Pro 5.1 2x2.97 6-core 32GB ram Aja I/O express, Apple... [view my complete system specs]
  • Sat, Apr 10 2010 5:37 PM In reply to

    Re: film 24fps - tk 25fps - sound - ??fps

    -The sync method you use does not have an impact.

    Symphony 7.06 OS 10.9.5 QT 7.6.3 Mac Pro 2x2.66 6-core 32GB Ram Aja Kona Lhi. MC 7.0.6 OS 10.9.5 Mac Pro 5.1 2x2.97 6-core 32GB ram Aja I/O express, Apple... [view my complete system specs]
  • Sat, Apr 10 2010 5:44 PM In reply to

    • jrp130
    • Not Ranked
    • Joined on Sat, Apr 10 2010
    • Posts 11
    • Points 155

    Re: film 24fps - tk 25fps - sound - ??fps

     

    i've been given these specs;

    788T - Reader
    48khz
    24fps
    24bit
    thanks again nubus. while i'm at it if use the audio tool to create 60 secs of tone i only end up with 57:15 of tone. can you explain why this is please.  as you can see i'm having trouble getting my head round the 24/25 concept!

  • Sat, Apr 10 2010 5:51 PM In reply to

    Re: film 24fps - tk 25fps - sound - ??fps

    Oh cripes, my understanding was not that secure... I am getting confused now.

    I am off to Waitrose before it closes. Who gave you the specs?

    I will think about it at the Deli counter

    David Y

    Symphony 7.06 OS 10.9.5 QT 7.6.3 Mac Pro 2x2.66 6-core 32GB Ram Aja Kona Lhi. MC 7.0.6 OS 10.9.5 Mac Pro 5.1 2x2.97 6-core 32GB ram Aja I/O express, Apple... [view my complete system specs]
  • Sat, Apr 10 2010 5:57 PM In reply to

    • jrp130
    • Not Ranked
    • Joined on Sat, Apr 10 2010
    • Posts 11
    • Points 155

    Re: film 24fps - tk 25fps - sound - ??fps

     

    ha ha...excellent, i admire you're honesty sir!!

    the sound recordist was the one with the specs - i'm hoping he's going to be the dialogue editor too as then it's his mess and he can sort it out!

     

    thanks again for your time david, pick up some donuts while you're there will you ;-)

     

  • Sat, Apr 10 2010 8:27 PM In reply to

    Re: film 24fps - tk 25fps - sound - ??fps

    jrp130:
    Camera 24, TK25 Audio timecode MUST be at 25fps

    Not really true. Used to be the best way for certain workflows. Not so much in the nonlinear days.

    (otherwise the dubbing theatre will get very upset

    incorrect.

    or, if the editor is doing audio sync in Avid, then if the audio timecode is 24fps the Avid will assume the project is NTSC and similarly get very upset

    Incorrect. Avid 24p project handle 24TC audio just fine. When you import the files, the Avid will even ask you whether your source is 24TC or 25TC.

    Also, you can copy/paste between 25TC and 24TC in Avid, and it will even recalculate.

    So yes, the net result is that in this day and age, it doesn't matter much.

    If you are cutting in HD, it would even be much more useful to have TC24 all over everything.

    The upside of your sound recordist using 24TC is that the timecode numbers on camera and sound will match.

    However, since you're syncing on sticks, you're good either way.

    Also, it is very easy to use tools like Wave Agent (IIRC) to change the metadata of the sound file, so that it will now divide each second into 25 steps, so a 25TC.

     

    Alternatively the location DAT could be cloned to a 25fps tape

    There you go. This confusion stems from the DAT era.

     

    while i'm at it if use the audio tool to create 60 secs of tone i only end up with 57:15 of tone

    I'm willing to bet that your Master timecode is set to TC1 (which is a 25TC counter), and therefore the duration is mentioned at 25 frames/sec. You should manually set it to TC24, and your duration will be calculated correctly. Unfortunately, you will have to manually switch to TC24 everytime you open the project, this setting does not stick.

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Sat, Apr 10 2010 9:46 PM In reply to

    • jrp130
    • Not Ranked
    • Joined on Sat, Apr 10 2010
    • Posts 11
    • Points 155

    Re: film 24fps - tk 25fps - sound - ??fps

     

     

    wow, thanks job for a most comprehensive reply.

     

    Incorrect. Avid 24p project handle 24TC audio just fine. When you import the files, the Avid will even ask you whether your source is 24TC or 25TC.

     

    this is great news but y avid didn't ask me anything, should i be concerned? like i say it's working fine now so i guess not but i'm just trying to eliminate any problems down the line.

     

    I'm willing to bet that your Master timecode is set to TC1 (which is a 25TC counter), and therefore the duration is mentioned at 25 frames/sec. You should manually set it to TC24, and your duration will be calculated correctly. Unfortunately, you will have to manually switch to TC24 everytime you open the project, this setting does not stick.

     

    i thought i had checked this but thanks for the reminder. so to calculate the true duration of the job for film out set it at tc24 and for dvd/tv version set to tc25 correct?

     

    thanks again all.

     

     

  • Sat, Apr 10 2010 9:55 PM In reply to

    Re: film 24fps - tk 25fps - sound - ??fps

    jrp130:
    avid didn't ask me anything, should i be concerned?

    You can do a simple check.

    The sound was apparently recorded with 24TC. Load a sound clip into your source monitor, and watch the A1 source timecode, while stepping through the clip. If it counts 1,2,3,4,5,6,7,8,9,11,13,14, etc (skipping frame 12, or any other frame number once every second) then you're OK, and the Avid is tracking a 24TC (actually TC25 with pulldown, but that's how it works in PAL 24p projects).

    If not (if there is no skipped frame number in the A1 source TC), copy the Start TC value into the TC24 column. When prompted, ask to Copy (not Convert) the TC. From then on, the TC24 column will track the correct TC24 for the clip. To copy the Start TC values for multiple clips, highlight the Start TC column and CMD-D (Mac) or CTRL-D (PC), then choose the destination column (TC24).

    jrp130:
    to calculate the true duration of the job for film out set it at tc24 and for dvd/tv version set to tc25 correct?

    Correct.

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Sat, Apr 10 2010 11:09 PM In reply to

    • jrp130
    • Not Ranked
    • Joined on Sat, Apr 10 2010
    • Posts 11
    • Points 155

    Re: film 24fps - tk 25fps - sound - ??fps

     

    ok great thanks Job, this is great stuff.

     

    i have already sub-clipped and synced up most takes, can i still do this change once the audio has been applied to it's corresponding picture take?

     

    i'm back at home now but will def check this first thing tomorrow am.

     

    cheers JB!

  • Sat, Apr 10 2010 11:27 PM In reply to

    Re: film 24fps - tk 25fps - sound - ??fps

    jrp130:
    i have already sub-clipped and synced up most takes, can i still do this change once the audio has been applied to it's corresponding picture take?

    Yes, no problem whatsoever. Whatever metadata you add to the original master clips will be added to any derived subclips/synclips/sequences that point to them.

    Media Composer /w Symphony option | PT-HD | Win7Pro64 HP | OSX MBP | ISIS5000 | Nitris DX | Artist Mix & Transport & Color | AJA T-Tap | Decklink... [view my complete system specs]
  • Sun, Apr 11 2010 12:59 PM In reply to

    • jrp130
    • Not Ranked
    • Joined on Sat, Apr 10 2010
    • Posts 11
    • Points 155

    Re: film 24fps - tk 25fps - sound - ??fps

     

    hi JB, 

    sorry to bug you but i tried some of the things you mentioned and came up blank.

     

    >>The sound was apparently recorded with 24TC. Load a sound clip into your source monitor, and watch the A1 source timecode, while stepping through the clip. If it counts 1,2,3,4,5,6,7,8,9,11,13,14, etc (skipping frame 12, or any other frame number once every second) then you're OK, and the Avid is tracking a 24TC (actually TC25 with pulldown, but that's how it works in PAL 24p projects).

    If not (if there is no skipped frame number in the A1 source TC), copy the Start TC value into the TC24 column. When prompted, ask to Copy (not Convert) the TC. From then on, the TC24 column will track the correct TC24 for the clip. To copy the Start TC values for multiple clips, highlight the Start TC column and CMD-D (Mac) or CTRL-D (PC), then choose the destination column (TC24).<<

     

    i didn't get any skipped frame and even doing what you said with the t/c copy to tc24 column it changes nothing. it didn't prompt for a copy/convert choice either.

     

    >>I'm willing to bet that your Master timecode is set to TC1 (which is a 25TC counter), and therefore the duration is mentioned at 25 frames/sec. You should manually set it to TC24, and your duration will be calculated correctly. Unfortunately, you will have to manually switch to TC24 everytime you open the project, this setting does not stick.<<

     

    also if i change my master tc to 24 my 60sec of tone is still 57:15 and moving forward 10fr measures as 9fr. how the heck am i going to work out how long this dam thing is!!??

     

    thanks,

    jrp

     

     

     

     

Page 1 of 2 (20 items) 1 2 Next >

© Copyright 2011 Avid Technology, Inc.  Terms of Use |  Privacy Policy |  Site Map |  Find a Reseller