7D vs zoom H4 and H4n sync test

Solution

Solution

Filming at 25p mode H4N audio and 7D video length matches perfectly! :thumbsup:

the different length issue only appears in footage filmed at 23,97fps to me, but NOT in 25p mode.

SOLUTION:
Film at 25p for perfect audio+video length matching
When shooting at 24p the audio track speed has to be streetched to 100.11% in Final Cut
 
Last edited:
did you do a 23.97 timeline?

I did a 9 -10 min clip the other day with the 7D and H4n with a seinheiser awesome mic hooked up to it for a sound test in a potential location (to see how much echo and see if the hum of the ac stuff was to horrid).

I just slated and lined up the marks in vegas, ran in sync the entire time.
 
Sure. framerate can only be set in an empty sequence, on sequences with content fps cannot be changed. On a new sequence go to its settings (by rightclick on the sequence name) and change the the FPS. Finally drag and drop your contents.
 
paquitonavas said:
Sure. framerate can only be set in an empty sequence, on sequences with content fps cannot be changed. On a new sequence go to its settings (by rightclick on the sequence name) and change the the FPS. Finally drag and drop your contents.
Click to expand...

So then this is more of a workflow issue than a hardware/gear issue.
 
Luis Caffesse said:
Looks solid as a rock to me - not even one frame of slippage seen in the FCP timeline.
The waveforms from the 7D and the H4n lined up perfectly.

7D recording 1080/24
H4n using the built-in mics recording in Stereo Mode at 48k/16bit.

The audio on this video is from the Zoom - I muted the 7D audio on the timeline.



So it seems to be that there are two things at play in past tests:
  1. It's possible the sync clock in the H4 has a tendency to drift, which seems to not be a problem in the H4n
  2. The 5Dm2 shooting at exactly 30fps as opposed to 29.97fps will cause sync issues with properly recorded audio,
    and will require a retiming of the audio file to sync up.
Click to expand...


So I watched your video and want to ask where you got the gorilla and how did you teach it to clap on command like that? I've been trying to train one I brought back from Costa Rica since bananas are cheaper than an assistant.
 
Why do people refer to a sync clock in the H4? As far as I know, there is no way to sync the H4 nor is there a way to get a sync signal out of the 7D either.

The 7D records at 48kHz from what I see. The 5Dm2 records at 44kHz. Drift is usually in either direction, like from clock Jitter, and not just one direction. Given that there is consistent time differential problems, it sounds like to me that the clock is not right in the Zoom.

Audio recording is pretty simple measurement. If you were getting drift, it would not be consistent always.

As one user pointed out, most of the time I get multiple audio projects from camera and field recorder, it's been FCP settings that have been the problem. Not the files.

I'd try setting the H4 to 44.1k for the 5D and retest.
 
OK, this is a weird one. Not sure what I'm doing wrong.

Did 10min take with 3 claps at beginning and 3 claps at end of take.
Camera at: 25p 1080p
Zoom H4N: 48khz,24bit

Compressed with MPEG Streamclip into: APPLE XDCAM EX 720P/25P

Pre-set FCP 6.0 on easy setup for project settings for XDCAM 720P/25P

Manually synced up footage from 1st clap wavforms. By end of the timeline the other wavforms WERE IN SYNC!! They synced up perfectly. HOWEVER....the actual sound was 11 frames behind, nowhere near any wavform peaks!!
Utterly stumped! Any ideas anyone please? have no idea if Im importing sound wrong.
 
OK - so if I used a 7D with a Zoom H4n - filming at 23.976FPS - and then imported the 7D footage + audio, and then the Zoom H4n's audio, into Adobe Premiere (I'm using a system running Win XP 32bit OS), I should have no sync issues so long as the Premiere timeline is 23.976FPS?
 
Jean Dantes said:
OK - so if I used a 7D with a Zoom H4n - filming at 23.976FPS - and then imported the 7D footage + audio, and then the Zoom H4n's audio, into Adobe Premiere (I'm using a system running Win XP 32bit OS), I should have no sync issues so long as the Premiere timeline is 23.976FPS?
Click to expand...

I second that question.

I'm considering an H4n and would like to know how to sync properly with my videos shot at 24p and edited in Premiere.
 
Filming at 25p mode H4N audio and 7D video length matches perfectly!

the different length issue only appears in footage filmed at 23,97fps to me, but NOT in 25p mode.

SOLUTION:
Film at 25p for perfect audio+video length matching
When shooting at 24p the audio track speed has to be streetched to 100.11% in Final Cut
Click to expand...

Hmmm...OK...so if I shoot 25p on the T2i I won't have a problem syncing sound from the H4N in post? Pardon my ignorance, but isn't 25p a PAL standard? Is it going to matter that I'm using a PAL standard for a project that is, ultimately, going to be shown mostly on NTSC devices?
 
ive shot plenty of stuff with the zoom h4n, and it syncs perfectly. Never gone over 10 mins so far, but i mena who has shots that long anyway if your doing film making?

If your doing something else other than film making, just get a camcorder and a rode videomic
 
T2i 23.976 with external sound card in Premiere CS4

T2i 23.976 with external sound card in Premiere CS4

First of all 29.97 on T2i syncs perfect in Premiere CS4 from external source.

23.97 on the other hand is weird- the wav is shorter than the mpeg.

If it is drop frame doesn't that mean that the video should be the shorter one?

Now I will have to stretch the wav out and try to find the percentage to match the click over a 10 min range. Anyone know the figure?
 
You must log in or register to reply here.
Back
Top