HDV superior then DVCPROHD?
- Thread starter Glenn_Gipson
- Start date
Digigenic
Well-known member
:thumbsup:
That's pretty much what I've been told.
As long as there are still mechanical/moving parts, there's still the probability something could go wrong with recording the data. Thus, the JVC's ProHD 100 is still prone such drop outs. Solid State on the other hand could still lose data while recording, but only in the event of a power/electronic malfunction.
Oh, and let's not forget about human error...but I think everyone who purchased a Sony HDV camcorder defined that :laugh:
That's pretty much what I've been told.
As long as there are still mechanical/moving parts, there's still the probability something could go wrong with recording the data. Thus, the JVC's ProHD 100 is still prone such drop outs. Solid State on the other hand could still lose data while recording, but only in the event of a power/electronic malfunction.
Oh, and let's not forget about human error...but I think everyone who purchased a Sony HDV camcorder defined that :laugh:
thisiswells
Retired
Yeah, compressed audio has an undesirable effect--mostly like HDV--completely undesired.
The HD100 is purported to have uncompressed audio.. which is a technical possibility due to the way the MPEG stream is recording both video and audio on the 19mbps portion of the tape where normally only video is recorded in DV. That leaves a remaining 6mbps space where audio is normally recorded for DV and historically has been left empty for HDV. So, that empty space is where HD100 is supposed to record uncompressed audio.
The problem with this is that audio is purported to have a 6-frame delay from video sync. So, audio and video are out of sync by 1/4 Second at 24 frames. Not good.
To re-cap:
Compressed audio in HDV=bad.
Uncompressed audio in HDV=bad.
brian wells
The HD100 is purported to have uncompressed audio.. which is a technical possibility due to the way the MPEG stream is recording both video and audio on the 19mbps portion of the tape where normally only video is recorded in DV. That leaves a remaining 6mbps space where audio is normally recorded for DV and historically has been left empty for HDV. So, that empty space is where HD100 is supposed to record uncompressed audio.
The problem with this is that audio is purported to have a 6-frame delay from video sync. So, audio and video are out of sync by 1/4 Second at 24 frames. Not good.
To re-cap:
Compressed audio in HDV=bad.
Uncompressed audio in HDV=bad.
brian wells
To me the biggest differences between DVCpro and HDV are:
1) The 4:2:2 color space. This is more important than many realize. I'd MUCH rather have twice as much chroma and slightly lower luminance (horizontally).
2) Motion artifacts including resolution loss
Those two things make DVCpro the winner in my book not counting the post trouble associated with editing MPEG2.
1) The 4:2:2 color space. This is more important than many realize. I'd MUCH rather have twice as much chroma and slightly lower luminance (horizontally).
2) Motion artifacts including resolution loss
Those two things make DVCpro the winner in my book not counting the post trouble associated with editing MPEG2.
Zig_Zigman
Well-known member
This camera might just take beautiful pictures. Audio can be fixed in post. Let's not rush to judge just yet.
Barry_Green
Moderator
In terms of original production, it definitely makes a difference. DVCPRO-HD (and the forthcoming variant of ProHD) record the audio uncompressed. Assuming all other things are equal (meaning, quality of the pre-amps, quality of the AtoD converters, etc) uncompressed audio will definitely be superior to MPEG-1 Layer II compressed audio.Feroxfilm said:
So during capture, the damage is done (with HDV/compressed audio). But in terms of post, well, it may or it may not make a difference, depends on what you're mastering out to. If you're mastering back to HDV, yes it'd involve more loss, which is bad. But if you're mastering to DVD, you can send it out to uncompressed PCM, or re-compress to AC-3, and those additional steps would need to be taken whether you started with compressed or uncompressed audio. So there may or may not be further complications in post.
But in acquisition, there's no question -- uncompressed beats compressed all day long, if all other things are equal (which remains to be seen).
Barry_Green
Moderator
The question you ask has multiple answers, depending on what you're recording to. If you're recording to DVCPRO-HD tape, it always records at 100mbps no matter what. 1080i and 1080p gets recorded as 60 fields, using 100mbps. 720p gets recorded as 60 frames, so if you're recording at a slower frame rate (such as 720/24p) it duplicates frames on tape to "pad" it up to 60, to make it compatible with the tape deck. That's the way the VariCam works.SergejIvanovits said:
Now, if you're recording through streaming firewire (or USB2?) to an external device, we don't know the official answer yet, but my guess would be that it will still be a full 100mbps stream. You'd want to maintain compatibility with any external recording device, including the existing AJ-1200HD tape deck, so you'd still want 100mbps.
As for recording on P2 cards? I'll bet a hundred bucks that it records only the data it needs... i.e., no duplicate frames. So 720/24p would be recorded at 40mbps.
As for your question about "more space for 1/24", no, that's not possible. With DVCPRO-HD, it's a frame-discrete compression system. Every frame is compressed to exactly the same size every time, just like DV. No frame is dependent on anything that happened on any other frame. So there's no more bits to spread around, it's frame-discrete. So a slower frame rate should (and I believe "would") result in less space necessary on the P2 card.
Barry_Green
Moderator
Same way all HD recording formats do. HDCAM and HDV use 1440x1080, and get digitally resized on output. DVCPRO-HD does the same thing, from 1440 (in 50i mode) or from 1280 (in 60i mode). The difference is that DVCPRO-HD has more color information than either of the other formats.evinsky said:
Barry_Green
Moderator
Well, let's examine that -- in 1080/50i mode, apparently DVCPRO-HD records at 1440x1080, so there's definitely no resolution advantage to HDV. Especially when you factor that DVCPRO-HD is recording twice as much color resolution!redindian said:
In 60i it's a little different. While you can say HDV technically offers 12.5% "more resolution" in a strictly luma sense (1440 vs 1280), don't forget that in terms of color, DVCPRO-HD offers 100% "more resolution". It has twice the color sampling of HDV.
And, when you factor in that HDV has no provision for 1080p recording at all, it's obvious that the P2 cam has a massive advantage. Having actual 24p/30p support in 1080 sure beats no support whatsoever, regardless of whether there's 160 pixels of difference or not.
Now, in 720p the numbers are different: HDV does encode 33% more luma pixels, but DVCPRO-HD still does 100% more color, so that's where it starts to look a lot more comparable. But then the question of variable resolution frames due to MPEG-2 compression come into play. That's a question that can only be answered by actually looking at the footage, something we can't do yet but will definitely be doing when both cameras are available for review.
redindian
Well-known member
Barry_Green said:
how do u know so much?!!?
You need to have a homepage like Adam Wilt... a FAQ, your book shop..etc... (I volunteer to design it
Googling your name we get to a bunch of 'CineForm' B-Gs
* Used Crane Salesman
* Oral Sensitivity Investigator
* Bassist in Cincinnati Symphony
* Professional Trombonist
* Algebra Professor
Barry_Green
Moderator
My favorite is the "professional trombonist". Dang, with a resume like that, I'd almost be as varied and skilled as Buckaroo Banzai. Which was an awful film, I must say. Although when Christopher Lloyd, in alien costume, flipped off the head alien, that was kinda funny...
Barry_Green said:
Is it fair to say that DVCPROHD has 100% more color resolution? As I see it, the color resolution breaks down like this:
1080i60 HDV: 4:2:0 sampling of 1080x1440 = chroma res of 540x720 = 388800 chroma pixels
1080i60 DVCPROHD: 4:2:2 sampling of 1080x1280 = chroma res of 1080x640 = 691200 chroma pixels
This works out to DVCPROHD having 78% more chroma resolution than HDV. Still impressive, but not quite 100%.
720p HDV: 4:2:0 sampling of 720x1280 = chroma res of 360x640 = 230400 chroma pixels
720p DVCPROHD: 4:2:2 sampling of 720x960 = chroma res of 720x480 = 345600 chroma pixels
This means 720p DVCPROHD has 50% more chroma resolution than HDV.
Totally agreed. Just thought I'd get in a little pedantry in the mean time. ;-)
Graeme_Nattress
Red Team
But if the lens of the camera is not up to the 1440 rez, or if the chips are not up to the 1440 rez, there's very little point using a codec that stores the 1440 rez. Just as we know that a high quality SD format will uprez to HD and look better than a low quality HD format, it's not resolution that counts but "definition" in a High Definition format, and definition is much more than resolution. VHS uprezzed to HD has HD resolution, but it does not have HD "Definition"! I want High Definition which implies high resolution at a high quality, not High Resolution which means nothing.
Graeme
Graeme
thisiswells
Retired
Whatever, Graeme. It's one and the same, you know better.
A "Magic Uprez" tool upfuzzes and there isn't a practical discussion over
high resolution vs. high definition.
All broadcast HD formats use a similar bitrate and compression as HDV.
Considering discussion of late has been con-HDV I don't think this is
reasonable considering all HD we have ever watched in our homes has
been on this quality level and no-one would actually prefer upfuzzed SD to
a broadcast OTA HD signal or HDsatalite or HDcable. SD programming upfuzzed
to HD does not look as good as real HD from a High-Def camera.
Try an Angenieux adapter with Ultra Primes if you're concerned about resolving power, man.
A "Magic Uprez" tool upfuzzes and there isn't a practical discussion over
high resolution vs. high definition.
All broadcast HD formats use a similar bitrate and compression as HDV.
Considering discussion of late has been con-HDV I don't think this is
reasonable considering all HD we have ever watched in our homes has
been on this quality level and no-one would actually prefer upfuzzed SD to
a broadcast OTA HD signal or HDsatalite or HDcable. SD programming upfuzzed
to HD does not look as good as real HD from a High-Def camera.
Try an Angenieux adapter with Ultra Primes if you're concerned about resolving power, man.
scharky
Veteran
thisiswells
I don't know, I think uprezzed footage from an SDX900 would beat the FX1 any day, and I know this isn't a fair comparison, its not supposed to be, you get what you pay for, but this is what you are saying.
Your other point doesn't make sense as well. Sure broadcast footage is about the same as HDV, but they don't start out like that. Lets bring it back down to SD resolution to show my point. Would you rather have to color correct and edit footage straight from the firewire out of the DVX, or after capturing broadcast footage from the television from a more expensive camera? Which would look better. We could even recapture footage from a DVD, and edit that, will it look as good? No. So the reason why many people don't want HDV including myself is because of this fact, that it is very very compressed footage, just like a final format broadcast. There is another poster on another forum that questions why his footage looks good from the FX1 from the camera, but when he CC it, all of these artifacts come to light. We all know the reason why. Granted, if you shoot for your final, and have litte editing to do,some really great footage can come from these cameras. However, the difference between HDV and DVCpro is night and day.
I don't know, I think uprezzed footage from an SDX900 would beat the FX1 any day, and I know this isn't a fair comparison, its not supposed to be, you get what you pay for, but this is what you are saying.
Your other point doesn't make sense as well. Sure broadcast footage is about the same as HDV, but they don't start out like that. Lets bring it back down to SD resolution to show my point. Would you rather have to color correct and edit footage straight from the firewire out of the DVX, or after capturing broadcast footage from the television from a more expensive camera? Which would look better. We could even recapture footage from a DVD, and edit that, will it look as good? No. So the reason why many people don't want HDV including myself is because of this fact, that it is very very compressed footage, just like a final format broadcast. There is another poster on another forum that questions why his footage looks good from the FX1 from the camera, but when he CC it, all of these artifacts come to light. We all know the reason why. Granted, if you shoot for your final, and have litte editing to do,some really great footage can come from these cameras. However, the difference between HDV and DVCpro is night and day.
Graeme_Nattress
Red Team
Sony were claiming at their Z1 demo that DSR570 footage uprezzed looks better than the Z1. As for "upfuzz" rather than "uprezz" - you need a new uprezzer! Good ones don't fuzz!
Actaully, I'd prefer uprezzed SD to the HD that we get in homes, as HD is broadcast with such an abysmally low data rate that artifacts abound and it looks bad. I'd much prefer that we got perfect SD to poor HD. That said, SD broadcasts are pretty abysmal in their compression too.
I'd also say that "high Definition" and "high resolution" are very different. One can have high resolution without high definition, but you cannot have high definition without high resolution.
Graeme
Actaully, I'd prefer uprezzed SD to the HD that we get in homes, as HD is broadcast with such an abysmally low data rate that artifacts abound and it looks bad. I'd much prefer that we got perfect SD to poor HD. That said, SD broadcasts are pretty abysmal in their compression too.
I'd also say that "high Definition" and "high resolution" are very different. One can have high resolution without high definition, but you cannot have high definition without high resolution.
Graeme
Barry_Green
Moderator
Broadcast footage is also not necessarily "acceptable" yet. For dramatic content it looks fantastic, but for sports, the motion artifacting was unnerving. During the whole NCAA basketball tournament, with the constant de-rezzing during fast pans and the variable-focus effect whenever they'd cut away, I kept asking "who thought this was a good idea?" During static or relatively static shots it was fantastic, but man, I sure wish the broadcast standard was at least twice the bitrate. Too late now, I know, but someone wasn't thinking it through all the way...
Haven't seen any basketball on Fox or ABC, it'd be interesting to see if 720p shows the same picture degradation.
Haven't seen any basketball on Fox or ABC, it'd be interesting to see if 720p shows the same picture degradation.
Jan_Crittenden
Veteran
thisiswells said:
That may be true for a HD broadcast data stream, not a production stream and these two ideas are absolutely different. HDCAM, DVCPRO HD, D5 HD uncompressed HD, use a much larger data stream than HDV in production. When it gets broadcast is the only place where is sees the low data rate that is seen in HDV. Starting there is not the best strategy as there is no margin for error.
Additionally the other HD signals that are at higher bitrates in production have a good deal more latitude as to where the end product will be used.
Best,
Jan