Mounting the Zoom H4 oncamers (hotshoe)

[Scott Brickert]

I'd like to experiment with mounting the Zoom H4 oncamera via the hotshoe adapter.

Option 1- use the tripod adapter that came with the unit, and add a hotshoe to 1/4"-20 male adapter. B&H has a hotshoe to 3/8" adapter, but I can't find one going to 1/4": Any ideas?

Option 2-use the Sennheiser CA2 Shoemount Adapter and velcro the H4 to that.

Other thoughts?

[Jay Massengill]

There are hotshoe to 1/4-20 adapters available, as well as small female 3/8-16 to male 1/4-20 adapters that could be added to the one you've already found. I can't offer any direct links, but photography stores and the B&H photography section are the most likely places to locate them. I've acquired a lot of these different adapters over the years.
My experience with my H4 has been that the onboard mics are extremely sensitive to handling and wind noise. Are you planning to use it that way or to be a better recorder for your external mics?
The H4 screen would also be hard to see in that position unless you're using the camera down low all the time.
I've used my H4 in a bag at chest level while doing audio, but I haven't used it while also operating a camera.

[Steve Leverich]

Try this one, I've used it for different things and it works OK -

http://www.bhphotovideo.com/c/produc...1_4_20_to.html

Steve

[Michael Liebergot]

I would just like to know, what is the reasoning to mount the H4 to your camera?

Doesn't that defeat the purpose of being close to your sound source in order to get a constant adn strong signal?

[Scott Brickert]

Hey Steve, thanks, that's what I was looking for.

Michael, yes, getting the mic close to the source is definitely the best, but in a fast action setting where nothing is under my control, I settle for bringing the mic with me. The H4 allows uncompressed recording, exceeding the MPEG1/LayerII built into the HDV codec.

This is an experiment. It may be that the H4 picks up too much camera noise for it to be useful on camera.

[Craig Irving]

I'm looking at purchasing the Zoom H4 recorder, but I'm wondering (and hopefully this isn't a dumb question) whether it's going to be problematic to sync this if I'm recording a film in 24P. Does the alternate frame rate affect anything?

[Steve House]

Originally Posted by Craig Irving

I'm looking at purchasing the Zoom H4 recorder, but I'm wondering (and hopefully this isn't a dumb question) whether it's going to be problematic to sync this if I'm recording a film in 24P. Does the alternate frame rate affect anything?

The camera frame rate won't affect anything but you're still going to have sync problems. The camera and the recorder aren't going to be talking to each other so there's nothing to lock them together. You didn't say what camera you have so I don't know the timecode situation with it will be but the Zoom doesn't do timecode anyway so there's no time reference in your audio file either - you'll need to slate your takes to establish a sync point. You can expect to not have too many headaches with short takes but you're liable to have drift over longer takes - how much is anyone's guess right now.

Something check out is the Zoom records at the standard CD sample rate of 44.1 kHz. But the DV standard is 48kHz and you'll need to sample rate convert when you import the audio into your editor. Normally this isn't a problem but not NLEs are equally adept at doing this so you need to check it out.

[Craig Irving]

Hmmm, that may be a problem then because aside from short films, I also do live concert recording, and those concerts I'll be recording continuous for approximately an hour.

I have an HVR-V1U so I'm hoping to bypass the MP2 audio compression that ensues with HDV. Will the Marantz have a sync problem also? What about the Sound Devices 744t, same thing?

Nevermind, I don't want to hijack the thread. I'll just continue to research :)

[Steve House]

Originally Posted by Craig Irving

Hmmm, that may be a problem then because aside from short films, I also do live concert recording, and those concerts I'll be recording continuous for approximately an hour.

I have an HVR-V1U so I'm hoping to bypass the MP2 audio compression that ensues with HDV. Will the Marantz have a sync problem also? What about the Sound Devices 744t, same thing?

I took another look at the Zoom specs and it will record at 48kHz so at that's not going to be a problem after all. Don't know which Marantz you're referring to.

You have the potential for sync drift anytime there's no connection between the camera sync and the audio recorder sync, either with a direct connection or through the use of tools such as Ambient Lockit boxes. But one the factors that accounts for the >10x difference in price between, say, the Zoom H4 and the SD744T is the accuracy of their electronics, including the stability of the clocks. How long a take you can manage without excessive drift will defintely be less with the Zoom than the SD but how much is hard to say. If your budget goes to the Sound Devices class of gear, unless you need to record 4 channels and prefer recording to an internal hard drive instead of a CF card, the 744T may be overkill. The 702 or 702T stereo recorders offer the same level of quality at significantly lower prices. Even more budget minded would be the Tascam HDP2, also timecode capable nd it accepts video sync as well.

[Gints Klimanis]

Originally Posted by Steve House

You have the potential for sync drift anytime there's no connection between the camera sync and the audio recorder sync, either with a direct connection or through the use of tools such as Ambient Lockit boxes. But one the factors that accounts for the >10x difference in price between, say, the Zoom H4 and the SD744T is the accuracy of their electronics, including the stability of the clocks.

The Zoom H4 is reputated be off by one second every thirty-nine minutes, which was a deal breaker for me. So, I ended up with the Edirol R4 pro.

[Scott Brickert]

I might occasionally need to record over 40 minutes. I wonder if it's a linear variation.

Here's an experiment I'll run when I get a chance.

Place the H4 on a table, with headphone out to the camera, eg HC7 or whatever, start both recording, then every ten minutes look into the camera and say something. When I bring the H4 audio onto the timeline and look at it, at 40 minutes, my lips will be moving, but the H4 audio will be early or late by around a second....? And, if it's a linear drift, that variation will have grown over the duration, so it will be off half as much at 20 minutes as at 40 minutes, and possibly 1.5x as much at 60 minutes...

[Steve House]

Originally Posted by Scott Brickert

I might occasionally need to record over 40 minutes. I wonder if it's a linear variation.

Here's an experiment I'll run when I get a chance.

Place the H4 on a table, with headphone out to the camera, eg HC7 or whatever, start both recording, then every ten minutes look into the camera and say something. When I bring the H4 audio onto the timeline and look at it, at 40 minutes, my lips will be moving, but the H4 audio will be early or late by around a second....? And, if it's a linear drift, that variation will have grown over the duration, so it will be off half as much at 20 minutes as at 40 minutes, and possibly 1.5x as much at 60 minutes...

I would expect it to be linear. An even more precise measure than lip movement would be to bang an old-fashioned clapper slate at the start of the tape and every 5 minutes or so thereafter.

This sort of drift is caused by slight variations in the sample clock rate between the clock in the camera and that in the recorder. DV audio is nominally a 48kHz sample rate. Assume for the moment that your camera is dead on. If your recorder's clock runs slightly faster than that, say 48,100 kHz, audio that was recorded for 1 second will have more samples than it should, in this case 48,100 samples. When you load it into your editor's timeline it will thus take a little more than one second to play back because there the first 48,000 samples in the audio data will take exactly 1 second to play back and after that 1 second there will still 100 be samples left to go -the audio has slowed down. If it turns out your camera is ALSO fast by the same amount, then both picture and sound will be affected equally and the streams will stay in sync. But if your camera's clock is slow, say 47,900 Hz, video will be speeded up while the audio is slowed, compounding the drift.

[Roger Shore]

I have found that this technique can help.