Record in HDV, DVCAM, or DV?

Tech Diver wrote on 7/19/2006, 2:18 PM
Until recently, DV was the only choice I had as format in which I could record. However, with the purchase of my new HVR-A1, I can record video as either HDV, DVCAM, or DV. The question is, which format should I use as "default". By that I mean, what format should I use when a specific requirement has not been defined for the task.

I have read articles that recording in HDV format and down-converting to DV through my camera will yield a better quality image than recording in DV format in the first place. If this is true, and we consider the fact that HDV does not take up any more tape storage than DV, then it would make sense to always shoot HDV rather than DV. The ability of my camera to place 4:3 guidelines on the 16:9 image helps this scenario. Any thoughts?

To slightly complicate matters, I also have the option of shooting in DVCAM format. I have read lots of post here about whether having fewer dropouts is significant or not. There did not seem to be a consensus. However, I do think that the ability to lock the audio to the video might be a good advantage. An obvious (but not serious) disadvantage of DVCAM is that it uses 50% more tape than the other formats.

So, should I "default" to HDV, DVCAM, or DV? Your opinions would be greatly appreciated.

Comments

jrazz wrote on 7/19/2006, 2:25 PM
I would default to HDV for one main reason: You will have the same footage later on tape in HDV if you ever want to use it for something that requires HDV as a prerequisite. For instance (this is hypothetical) That dive you made, you had an awesome shot of an octopus chasing a barricuda down by the reef... You would like to include it in video you are trying to market to the discovery channel but all they take is HDV. You can't use that footage b/c it is standard def.

You can always downconvert, but you cannot get a true upconvert. I would default to HDV, especially since that is where everything seems to be going.

j razz
Tech Diver wrote on 7/20/2006, 9:18 AM
Thanks JRazz for the feedback. I kind of figured that HDV was the format of choice between the three, but I needed someone to confirm it. As for the other two, I'm still a bit confused whether DVCAM has any virtues over DV. Like I said, previous postings seemed inconclusive.
JohnnyRoy wrote on 7/20/2006, 9:26 AM
I would always shoot HDV for the reasons jrazz gave.

> I'm still a bit confused whether DVCAM has any virtues over DV.

The virtues of DVCAM are fewer dropouts. The tape runs faster therefore a bad piece of tape is under the heads for less time and produces a smaller dropout.

~jr
farss wrote on 7/20/2006, 2:21 PM
Also DVCAM offers true time code which DV does not however with Vegas that seems to be worthless.
The dropout difference I think is more due to a wider track being written, a wider track means the data is written to more of the media so if a piece of the media flakes off there's less chance of data loss. The wider track means the tape has to move faster and hence less record time.

Bob.
Tech Diver wrote on 7/20/2006, 4:36 PM
How about the ability of DVCAM to lock audio to video? Is the use of this dependent on the ability of the editor to support true time code?

If I interpret correctly what you guys are saying, it sounds like DVCAM is a better choice over DV if you don't mind the shorter record times of the tape cassettes.
PeterWright wrote on 7/20/2006, 5:27 PM
Although theoretically DVCam is a more robust way of storing and retrieving data from tape, in practice it's extremely rare to get any dropouts with normal DV, and the picture quality is exactly the same.

And whether it's technically "locked" or not, the audio I capture with DV has always fitted the video that comes with it!
GlennChan wrote on 7/23/2006, 12:02 PM
Some NLEs can't handle unlocked audio well... FCP can be like this if you set the settings wrong and shoot with something like the XL1. It can slip out of sync if you have really long clips.

Unlocked audio has never been a problem with Vegas AFAIK.
farss wrote on 7/23/2006, 3:00 PM
Certainly Vegas has no issue with unlocked audio, at least I've never heard of one.
The unlocked audio is simply a relaxation of the spec that permits audio data block to be written a few frames after the vision, I believe most DV devices today don't need this latitude anyway.
Where it was an issue was with linear editing i.e. tape to tape. Imagine doing an insert edit starting at say frame 5 when the audio for frame 5 is in frame 7.

Bob.
Steve Mann wrote on 7/24/2006, 3:56 PM
Audio sync is unrelated to locked audio. (See Adam Wilt's site for info: http://www.adamwilt.com/DV-FAQ-tech.html#LockedAudio)

The FCP audio drift is another problem altogether.

In reality, it's extremely unlikely that any of us will ever see an inlocked audio issue with our typical DV cameras.

Steve M.
GlennChan wrote on 7/24/2006, 5:34 PM
The FCP audio drift is another problem altogether.
From my reading of Adam Wilt's DV FAQ, it seems that FCP audio drift is related to locked/unlocked audio. Anyways, it's a moot point- just read the FAQ for yourself.

it's extremely unlikely that any of us will ever see an inlocked audio issue with our typical DV cameras.
Some (but not all) cameras with unlocked audio can lead to the FCP losing sync problem... see above.
farss wrote on 7/25/2006, 2:43 AM
That's a heck of a lot to digest on one reading but at last I think I have my head around it. Might just explain some odd things I've had happening audio wise from early FCP systems, what sound like minor sample rate errors, hmm.

So we can assume that Vegas is smart enough to reclock audio from the cameras that are a bit on the dodgy end of the spec?

I've certainly captured over 4 hours from one DV tape but the content didn't lead itself to checking sync.

Bob.
GlennChan wrote on 7/25/2006, 4:22 PM
So we can assume that Vegas is smart enough to reclock audio from the cameras that are a bit on the dodgy end of the spec?
Yep, basically. I haven't ever seen Vegas lose sync.
Tech Diver wrote on 7/25/2006, 5:04 PM
So if audio/video locking is not an issue with Vegas and dropouts are fairly rare with good quality tapes, then there does not appear to be an overwhelming advantage of using DVCAM over DV. Furthermore, the reduction in available recording time due to the faster tape transport speed is a disadvantage that might outweigh any small improvements in dropouts that DVCAM offers. Any thoughts?
GlennChan wrote on 7/25/2006, 6:44 PM
DVCAM tape is pretty dirt cheap, so that may not be too big a deal.

DVCAM does allow things like linear editing... which some people still do because it's faster (news, packaging, formatting masters). Other than that, it's probably not a big deal.

Dropouts do happen though (i.e. dust)... DVCAM is presumably more robust here.