-
Low cost Zoom or Tascam portable recorders’ frame rate
I don’t have the budget to rent or buy the Zaxcom TRXLA2 series with built in recorder and receiver for lav mic confidence monitoring. Thus I have to use Sennheiser G3 tx & rx. I’ll shooting lots of hiking footage at remote locations and can’t bring big cams nor sound bag. It’s just a 2 person crew. Have to be super lightweight and at a bare minimum gearwise. The frame rate of the shoot will be 29.97 NDF on the POV cams. If I use the Tascam or Zoom portable recorder (<$200), what is the default frame rate for those recorders? Does it even matter?
Hand clapping over SMPTE TC is the only way to properly sync this. It will work but not the most efficient or elegant method.
-
3 Replies
-
Yes and no. There is no “frame-rate” in audio recorders. There IS a “Sample-Rate” which is the audio equivalent. For example your video frame-rate is 25 of 30 or 50 or 60 FPS (or the slightly lower “NTSC” rate like 29.97, etc.)
But the standard audio SAMPLE-RATE is 48 thousand samples (48K) per second, regardless of the video frame rate.
IMHO, the three most critical things in selecting a separate audio recorder are:
1) Sample-rate accuracy. If you have a combination of audio recorder and video camera that don’t match with reasonable accuracy, you will be slipping out of sync in a matter of a few minutes. This may not be a problem for short shots. Or even for longer shots where you will be intercutting “B-roll” video clips or maybe be even for shots where lip-sync is not important. If the dialog is “voice-over” narration or you are doing “over the shoulder” shots where you can’t see the subjects lips, etc.
2) Sample-rate selection. My very strong preference would be for a recorder that allows 48 KHz sample rate. Most low-cost recorders use the slightly slower 44.1 KHz or even lower for simple utility “voice recorders”. Now, you can re-sample audio from 44.1K up to 48K, and some video editing software even does this for you. But any time you have to re-sample something means a potential loss of quality. Not to mention the extra time it takes.
3) Data compression. I would have a very strong preference for an audio recorder that will store the audio as UN-compressed WAV (or AIFF, etc.) files, and NOT MP3 or other kinds of compressed format. Any time you have to un-compress something (in order to edit it), and then re-compress something (for distribution), you run a significant risk of loss of quality. In extreme cases, rendering audio that is unusable.
-
With those unfavorable parameters for the cheap $200 recorders, I had a chance to take a closer look at my good old Sound Devices 702T. It’s actually pretty small when taken out of the bag and stripped off all of the data i/o. Much lighter than an Anton Bauer Hytron 140 battery. I’ll have 100% accurate sound recording.
I’ve edited films where the sound recordist recorded at 29.97NDF and the cam was at 23.98PN. It’s a nightmare after 4 minutes into the long take. A pound more of weight in the field will be a sacrifice for the post. Boy it’ll make hiking up hill a bit harder than 1/4 lbs with the pocket recorder. Talk about out of physical shape. Most in good physical shape folks would laugh at this!
-
I’ve edited films where the sound recordist recorded at 29.97NDF and the cam was at 23.98PN. It’s a nightmare after 4 minutes into the long take.
That is because they are diddling the sampling rate to try to compensate. I hate it when machines think they are smarter than us. To be sure, if you are shooting in some exotic format, testing everything before you start shooting is an absolute prerequisite.
Reply to this Discussion! Login or Sign Up