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View Full Version : Has anyone used a Zoom H4N with GH1?



rundavids
11-18-2009, 08:24 AM
Hi, does anyone know if it's difficult to sync sound with a separate audio recorder like the Zoom H4N to the GH1 camera? With the 24p, 60i, removing pulldown to 23.976 framerates; it all confuses me of what settings the Zoom H4N should have.

ydgmdlu
11-18-2009, 08:28 AM
Sound doesn't have a frame rate. Think about it. Just record 16-bit at 48 KHz (48000 Hz), and you'll be fine, regardless of what frame rate you choose for the video.

jamesc
11-18-2009, 08:51 AM
I use it all the time with mixed footage, works great for all the doc/narrative work I've shot so far. I really recommend getting pluraleyes as well, will save you an enormous amount of time.

rundavids
11-18-2009, 02:27 PM
Thanks for reply guys.

Indyreel
11-18-2009, 07:17 PM
Sound doesn't have a frame rate. Think about it. Just record 16-bit at 48 KHz (48000 Hz), and you'll be fine, regardless of what frame rate you choose for the video.

Why wouldn't you use the 24 bit setting?

ydgmdlu
11-19-2009, 12:58 PM
Why wouldn't you use the 24 bit setting?
Sure, you could use that. But why would you? Do you really need 24-bit? 16-bit is the industry standard (for motion pictures), and it's the most compatible with NLEs.

stoneinapond
11-19-2009, 02:09 PM
Sure, you could use that. But why would you? Do you really need 24-bit? 16-bit is the industry standard (for motion pictures), and it's the most compatible with NLEs.

Then why would you want to shoot 1080? TV standard is 720.

Answer is resolution. 24-bit dithered down to 16-bit is better than straight 16-bit audio. But then I'm an audio guy. :bath:

ydgmdlu
11-19-2009, 02:41 PM
Then why would you want to shoot 1080? TV standard is 720.

Answer is resolution. 24-bit dithered down to 16-bit is better than straight 16-bit audio. But then I'm an audio guy. :bath:
No...

1) TV standard is not 720. HDTV broadcast has two standards, 1080i and 720p. Most mid-range and high-end TVs are 1080p.

2) Some filmmakers here are not shooting for TV. They hope to eventually get theatrical distribution or exhibition, so 1080p would be optimal for that. They might also want Blu-ray distribution, and Blu-ray titles are most commonly mastered at 1080p.

3) A lot of people prefer to shoot 720p60 on their GH1s, simply because of decreased mud and rolling shutter artifacts. For them, the difference in effective resolution between the 720p and 1080p modes is not enough to justify the additional hassles of working at the higher nominal resolution.

I don't disagree with you at all about the audio. But the OP wanted a quick, straightforward answer. 16-bit acquisition is good enough if one isn't trying to be obsessive about sound quality. But then, if one is obsessive, then perhaps the H4n isn't the best choice of recorder to use, anyway...

stoneinapond
11-19-2009, 03:03 PM
No...

1) TV standard is not 720. HDTV broadcast has two standards, 1080i and 720p. Most mid-range and high-end TVs are 1080p.

2) Some filmmakers here are not shooting for TV. They hope to eventually get theatrical distribution or exhibition, so 1080p would be optimal for that. They might also want Blu-ray distribution, and Blu-ray titles are most commonly mastered at 1080p.

3) A lot of people prefer to shoot 720p60 on their GH1s, simply because of decreased mud and rolling shutter artifacts. For them, the difference in effective resolution between the 720p and 1080p modes is not enough to justify the additional hassles of working at the higher nominal resolution.

I don't disagree with you at all about the audio. But the OP wanted a quick, straightforward answer. 16-bit acquisition is good enough if one isn't trying to be obsessive about sound quality. But then, if one is obsessive, then perhaps the H4n isn't the best choice of recorder to use, anyway...

You're detailed response is fair. I was just trying to make a quick point. And yes, the H4n would not be my choice either.

Ozpeter
11-20-2009, 02:00 PM
24-bit dithered down to 16-bit is better than straight 16-bit audio.With the Zoom recorders it would enable you to make a more accurate recording of the noise in the analog stages, but I wouldn't describe that as a 'better' recording.

The practical use of 24 bits with such devices is to enable you to record with levels set conservatively (safe against overloads) peaking to (say) only -12dB and then to normalize the levels later, with no discernible quality loss.

noirist
11-21-2009, 08:23 AM
Sound doesn't have a frame rate. Think about it. Just record 16-bit at 48 KHz (48000 Hz), and you'll be fine, regardless of what frame rate you choose for the video.

Sound doesn't have a frame rate but a digital sound recording does have a frame rate. It's called the sampling rate (eg., 48,000 samples per second).

ydgmdlu
11-21-2009, 12:12 PM
Sound doesn't have a frame rate but a digital sound recording does have a frame rate. It's called the sampling rate (eg., 48,000 samples per second).
Yes, I know, but it's still not a "frame rate." Let's not confuse the terminology here.

The point is that video frame rate has no bearing on the sound. Audio sampling rate is a completely unrelated matter.

Barry_Green
11-21-2009, 12:37 PM
Let's clarify something -- the reason the "frame rate" has historically caused problems with sync'ing audio in editing, is because people have not been editing the video footage at the same frame rate it was shot at! They change the frame rate in editing. How? Well, let's say they shot film on a crystal-controlled camera at 24.000 fps. They then edit on a 23.976 timeline, and -- boom, sync errors. Or, they shoot on a 5D Mark II at 30.000 fps, and try editing on a 29.97 timeline -- boom, you'll have sync errors.

You have sync errors because the footage is no longer running at the same frame rate it was shot at. That's where the problem comes in. An hour's footage now runs in 59 minutes, etc.

If you edit the footage at the same frame rate you shot it at, then it will run exactly the same amount of time, and you will have no problems sync'ing. (assuming, of course, that your camera actually runs at a consistent speed, and your recorder does too).

So now let's apply it to "frame rates" for audio:
What if you shot a 5D Mark II at 30.000 fps, and edited at 30.000 fps... will the Zoom sync? Of course it will. A minute's worth of Zoom audio will play back in a minute, a minute's worth of 5DMkII 30fps footage will play back in a minute -- no sync error.

What if you shot a 7D video at 23.976 fps, and edited at 23.976 fps -- will the Zoom sync? Of course it will. Audio doesn't have a "frame rate", it doesn't care what the timeline is.

What if you shot an EX1 video at 59.94 fps, and edited at 59.94 fps -- will the Zoom sync? Of course it will.

What if you shot a GH1 video at 720/59.94 fps and conformed it in FCP to 60 fps, and edited on a 60.000 timeline -- will the Zoom sync? Of course not. You changed the running time of the video! An hour's video will now run in 59 minutes (or something), so no, the Zoom won't sync. Had you left the video at 59.94 and edited at 59.94, it would have sync'd.

rundavids
11-21-2009, 01:12 PM
Is the GH1s 1080p recording at 24fps or 23.97?

Barry_Green
11-21-2009, 01:36 PM
23.976.

No conventional video camera uses 24.000 fps. You'd have to go to a specialized camera like the VariCam or a digital cinema camera like the Red to get that kind of option.

rundavids
11-21-2009, 01:38 PM
I was wondering if I record sound on both the Zoom H4n and on my DSLR and use a clapboard; could I just sync the frame from the sound spike in post and delete the audio from the DSLR and just use the H4n?

Barry_Green
11-21-2009, 01:48 PM
Yes, you should certainly be able to do that. It may not hold absolute perfect sync over a very long take but it should be reasonably in sync, and may indeed be perfectly in sync.

rundavids
11-21-2009, 02:07 PM
Would that be a good way to sync sound, or is there another way that could be easier? Most clips will be under 2 minutes.

Barry_Green
11-21-2009, 06:04 PM
clap at the start of each take.

If you want it automated, look into PluralEyes.