IEEE vs mini dv quality
- Thread starter pete66
- Start date
Re: IEEE vs mini dv quality
No, because the signal is compressed before it exports through either firewire or to tape. You're still dealing with a DV signal of 4:2:2 compression, unless of course you use that new device that is supposed to bypass the compression circuit in the DVX rendering you with an uncompressed raw signal.
No, because the signal is compressed before it exports through either firewire or to tape. You're still dealing with a DV signal of 4:2:2 compression, unless of course you use that new device that is supposed to bypass the compression circuit in the DVX rendering you with an uncompressed raw signal.
Barry_Green
Moderator
Re: IEEE vs mini dv quality
For clarification, the DV signal is 4:1:1 compression.
Technically there should be no difference whatsoever. The only place a difference would come in is if the tape was hit by a "dropout", something that theoretically should never affect a direct hard-disk recording.
For clarification, the DV signal is 4:1:1 compression.
Technically there should be no difference whatsoever. The only place a difference would come in is if the tape was hit by a "dropout", something that theoretically should never affect a direct hard-disk recording.
S
Sofa_King_Smart
Guest
Re: IEEE vs mini dv quality
Technically, though, Barry, going straight to HD should, in theory, have a slightly better output. THis is due to head to tape transmission coding. (You will not find this in any manufacturers literature, for what will soon be obvious) There is a "gap" between the taping head and the dv tape. It is small, like portions of a micron, but in that gap some really strange vortexi(sp?) takes place. Oh, sure, the signal is encoded onto the tape...we see this everytime we use the dv camera. But if you were to interrupt the signal BEFORE it were to get to the tape heads and compare it with the signal AFTER taping, there is a slight degradation; even with the dv compression algorithms. It is slight, I and some collegues tested this at our local University, but it is there. THerefore, going straight to HD without going through DV tape is better. (As a side note, we were looking for magnetic fields to capture on specially designed polaroid film. I suggested on the tape head because I had an old Canon l1 that was busted and ready for the trash or some "unusual" application. Very unusual application as it turned out.)
Even though we think of DV as digital tape, it is, as the data is stored on the tape as 1s and 0s, but it is encoded with a magnetic head.
Technically, though, Barry, going straight to HD should, in theory, have a slightly better output. THis is due to head to tape transmission coding. (You will not find this in any manufacturers literature, for what will soon be obvious) There is a "gap" between the taping head and the dv tape. It is small, like portions of a micron, but in that gap some really strange vortexi(sp?) takes place. Oh, sure, the signal is encoded onto the tape...we see this everytime we use the dv camera. But if you were to interrupt the signal BEFORE it were to get to the tape heads and compare it with the signal AFTER taping, there is a slight degradation; even with the dv compression algorithms. It is slight, I and some collegues tested this at our local University, but it is there. THerefore, going straight to HD without going through DV tape is better. (As a side note, we were looking for magnetic fields to capture on specially designed polaroid film. I suggested on the tape head because I had an old Canon l1 that was busted and ready for the trash or some "unusual" application. Very unusual application as it turned out.)
Even though we think of DV as digital tape, it is, as the data is stored on the tape as 1s and 0s, but it is encoded with a magnetic head.
Re: IEEE vs mini dv quality
[quote author=Sofa_King_Smart link=board=Events;num=1108330790;start=0#3 date=02/14/05 at 12:18:08]Technically, though, Barry, going straight to HD should, in theory, have a slightly better output. THis is due to head to tape transmission coding. (You will not find this in any manufacturers literature, for what will soon be obvious) There is a "gap" between the taping head and the dv tape. It is small, like portions of a micron, but in that gap some really strange vortexi(sp?) takes place. Oh, sure, the signal is encoded onto the tape...we see this everytime we use the dv camera. But if you were to interrupt the signal BEFORE it were to get to the tape heads and compare it with the signal AFTER taping, there is a slight degradation; even with the dv compression algorithms. It is slight, I and some collegues tested this at our local University, but it is there. THerefore, going straight to HD without going through DV tape is better. (As a side note, we were looking for magnetic fields to capture on specially designed polaroid film. I suggested on the tape head because I had an old Canon l1 that was busted and ready for the trash or some "unusual" application. Very unusual application as it turned out.)
Even though we think of DV as digital tape, it is, as the data is stored on the tape as 1s and 0s, but it is encoded with a magnetic head. [/quote]
There CAN’T be a difference. It doesn’t work like that. What you describe makes a difference in analog recording, but not in digital recording.
Digital data are all 1s and 0s. You can’t record half of a 1 or half of a 0. As long as you have all of the 1s and 0s, you get the full quality. If a 1 or 0 isn’t recorded “all the way” or only “slightly,” it isn’t recorded at all, and you get a dropout (as vovka points out, a little block. The rest of the picture is unaffected). There’s no partial or “slight” recording. You have it or you don’t.
[quote author=Sofa_King_Smart link=board=Events;num=1108330790;start=0#3 date=02/14/05 at 12:18:08]Technically, though, Barry, going straight to HD should, in theory, have a slightly better output. THis is due to head to tape transmission coding. (You will not find this in any manufacturers literature, for what will soon be obvious) There is a "gap" between the taping head and the dv tape. It is small, like portions of a micron, but in that gap some really strange vortexi(sp?) takes place. Oh, sure, the signal is encoded onto the tape...we see this everytime we use the dv camera. But if you were to interrupt the signal BEFORE it were to get to the tape heads and compare it with the signal AFTER taping, there is a slight degradation; even with the dv compression algorithms. It is slight, I and some collegues tested this at our local University, but it is there. THerefore, going straight to HD without going through DV tape is better. (As a side note, we were looking for magnetic fields to capture on specially designed polaroid film. I suggested on the tape head because I had an old Canon l1 that was busted and ready for the trash or some "unusual" application. Very unusual application as it turned out.)
Even though we think of DV as digital tape, it is, as the data is stored on the tape as 1s and 0s, but it is encoded with a magnetic head. [/quote]
There CAN’T be a difference. It doesn’t work like that. What you describe makes a difference in analog recording, but not in digital recording.
Digital data are all 1s and 0s. You can’t record half of a 1 or half of a 0. As long as you have all of the 1s and 0s, you get the full quality. If a 1 or 0 isn’t recorded “all the way” or only “slightly,” it isn’t recorded at all, and you get a dropout (as vovka points out, a little block. The rest of the picture is unaffected). There’s no partial or “slight” recording. You have it or you don’t.
S
Sofa_King_Smart
Guest
Re: IEEE vs mini dv quality
What if a 1 is transposed as a 0? Or vice versa? What if this is done, say once every 200,000 hertz?
Answer, the built in ADC/DAC software compensates...but at what cost to quality?
What if a 1 is transposed as a 0? Or vice versa? What if this is done, say once every 200,000 hertz?
Answer, the built in ADC/DAC software compensates...but at what cost to quality?
S
Sofa_King_Smart
Guest
Re: IEEE vs mini dv quality
It is a factor of the magnetic head laying down the 1's and 0's, not of the tape being in digital format.
It is a factor of the magnetic head laying down the 1's and 0's, not of the tape being in digital format.
Re: IEEE vs mini dv quality
How could a 1 be transposed as a 0? And more importantly, how could a 1 be transposed as a 0 because of the distance between the head and the tape?
Sorry; I think you imagined your test results. It just doesn't work like that.
But if I'm wrong, go ahead and post them, because I'd love to see it.
How could a 1 be transposed as a 0? And more importantly, how could a 1 be transposed as a 0 because of the distance between the head and the tape?
Sorry; I think you imagined your test results. It just doesn't work like that.
But if I'm wrong, go ahead and post them, because I'd love to see it.
S
Sofa_King_Smart
Guest
Re: IEEE vs mini dv quality
You wouldn't understand what you'd be looking at anyway...
As for the transposition of digitization...stick to film malking if you're good at that...because EE and theoretical EE you don't stand a chance!
You wouldn't understand what you'd be looking at anyway...
As for the transposition of digitization...stick to film malking if you're good at that...because EE and theoretical EE you don't stand a chance!
Re: IEEE vs mini dv quality
Try me. At the very least, I'll learn something, won't I?
Try me. At the very least, I'll learn something, won't I?