DVCproHD-DVCpro50-DVCpro25

smelni

smelni

Veteran
I really tried to search the boards for an answer to this and just couldnt find.

Can someone help me understand the differences in the three formats DVCproHD-DVCpro50-DVCpro25 or point me to a reference that will help me?

I am trying to understand the benefits and costs associated with each format

thanks
seth
 
DVCPRO 25 and DVCPRO 50 are both SD formats:

DVCPRO 25 uses the same codec as standard DV, but when recording to tape, runs the tape faster in order to lay down a more stable track (just like DVCAM). However it is still exactly the same quality as DV & DVCAM. It uses 4:1:1 colour, meaning the colour is only recorded at a quater the 720x576 luma (black and white) resolution. It is compressed 5:1, 25 Mbits/sec or 3.6Mbytes/sec. In PAL land it is slightly different as DVPAL uses 4:2:0 and DVCPRO 25 PAL is still 4:1:1. It CAN be recorded onto DV tape on the HVX

DVCPRO 50 is superior: 4:2:2 colour (half colour resolution), 50 Mbits/sec. It rivals DigiBeta in terms of quality but cameras tend to be cheaper. On the HVX DVCPRO 50 can only be recorded on P2 or externally, ie NOT to tape!

DVCPRO HD has different "modes" and is a HD codec. It can achieve 1280x720 at 60 frames per second, always progressively scanned. It can also shoot 1920x1080 at up to 30 frames/sec (fps). This resolution is recorded as an interlaced stream, but can carry a progressive picture, like the DVX does on a DV footage stream. These "modes" are referred to as 720p and 1080i. The HVX can record both ONLY TO P2 or external device, NOT tape.

Just to confuse you, DVCPROHD actually records the data at lower resolution as a form of compression, it is then uprezzed on playback. The data rate can vary from 40Mbits/sec for 720p at 24 fps upto 100Mbits/sec for 720p @ 60fps or 1080i @ 30 frames/60 fields per second (60i).


Anyone please add to or correct me... I am sure I slipped up somewhere in all that typing!
 
mmm - thanks so much - that was great.

I understood DVCproHD but for some reason i thought those other formats were lower quality HD - but you straightened me out.

thanks again
 
dvcpro 25

dvcpro 25

Can the dvc25 use the 24p also and will the quality of video rival what the 100a puts to 24p. also is there a standard dv and then a dvc25 that can be put to tape or is it just the one dvc25?
 
The only thing that goes to tape, ever, under any circumstances, is miniDV.

The camera can shoot 24p in every mode it has. So yes, DVCPRO25 can use 24p, just like DV, DV50, and DV100.

As to whether the quality rivals that of the DVX100A, we'll have to see. The cadence/motion will be identical, but this camera has different chips, different image processing, etc. It may be comparable, it may be better, it may not be. In an interview, Jan said it would be better.
 
Sorry, just spotted an error I made above! NTSC DV is 4:1:1 but NOT 720x576, that is PAL resolution. I automatically think 720x576 because I am a PAL man.

Silly me!
 
DV NTSC: 720x480, 5:1 compression, 4:1:1 color sampling, 59.94 fields per second
DV PAL: 720x576, 5:1 compression, 4:2:0 color sampling, 50 fields per second

DVCPRO25 NTSC: same as DV NTSC
DVCPRO25 PAL: 720x576, 5:1 compression, 4:1:1 color sampling, 50 fields per second

DVCPRO50 NTSC: 720x480, 3.3:1 compression, 4:2:2 color sampling, 59.94 fields ps
DVCPRO50 PAL: 720x576, 3.3:1 compression, 4:2:2 color sampling, 50 fields ps

All DV and DVCPRO25 formats occupy 25 megabits per second. DVCPRO50 formats occupy 50 megabits per second.

DVCPROHD-720p: 960x720, approx. 6.7:1 compression, 4:2:2 color, 1.67 megabits per frame, at variable frame rates from 4 to 60 frames per second

DVCPROHD-1080/60i: 1280x1080, approx 6.7:1 compression, 4:2:2 color, 3.33 megabits per frame
DVCPROHD-1080/50i may be 1440x1080 or it may be 1280x1080, not sure. 4 megabits per frame
 
DVCPROHD has *more* compression than DVCPRO25/50? Does it not introduce compression artifacts?

Like a highly compressed JPG may be smaller in size, but has blockiness that is inherent with compression, unless its a non-destructive compression like WinZip.
 
DVCPRO50 is extremely mild compression. Nearly artifact-free, and holds up very, very well to recompression.

DVCPRO-HD has to fit 4x as many pixels into twice as much bandwidth. Obviously the compression ratio needs to be higher to accomplish that.

DVCPRO-HD can have similar mosquito-noise artifacts as DV does, but since the pixels are 1/4 the size, it's much less noticeable.
 
New registered user, but old time browser. I am definitly going to buy the hvx200, it's a great leap for the indie world. Barry just one question - why is the PAL DV mode 4:2:0 colour sampling and the NTSC 4:1:1? - is the american color range more or am I just getting my math wrong??(btw hows the g35 testing going?)
 
Yas Kassana said:
why is the PAL DV mode 4:2:0 colour sampling and the NTSC 4:1:1? - is the american color range more or am I just getting my math wrong??(btw hows the g35 testing going?)
Click to expand...

PAL DV is always 4:2:0 unless it is DVCPRO25 which is 4:1:1.

4:1:1 and 4:2:0 carry the same amount of colour information but slightly differently. 4:1:1 carries a quater of the colour resolution on each line, 4:2:0 carries half the resolution but on every second line.

See this link for a better explaination
 
So given the very small compression of DVCpro50 - which would you choose for a project that will be blown up to 35mm -

DVCpro50 or DVCproHD?
 
I haven't seen them blown up to 35 mm, but I presume DVCPRO HD. The greater resolution should really help on a big screen and artifacting shouldn't be too bad. Remember that DVCPRO HD at 1080p is recording TWICE the data of DVCPRO50.
 
Agreed -- it sure seems logical that the DVCPRO-HD would be the better format for film blowup. However, testing remains to be done to prove conclusively, one way or the other.
 
Again sorry for the ignorance - what is the colour sampling rate of the dvx100a?

Reason i ask is that, i will buy the hvx200, but will use DV for about a year(as i have not invested in a dvx100) wait for emerging technolgies to catch up and then get my P2 cards.
 
Yas Kassana said:
Again sorry for the ignorance - what is the colour sampling rate of the dvx100a?

Reason i ask is that, i will buy the hvx200, but will use DV for about a year(as i have not invested in a dvx100) wait for emerging technolgies to catch up and then get my P2 cards.
Click to expand...

That makes sense.

DVX100A records a DV stream to mini DV tape. That is 4:1:1 or 4:2:0 if you are a PAL man like me. The HVX will be the same when recording on tape (but with DVCPRO25 the tape runs faster in order to increase reliability).

To get 4:2:2 it will require P2 cards or external recording device.
 
DVCPRO25 on tape is not an option with the HVX. DVCPRO25 is only applicable to P2 recording or firewire streaming. In those cases, the only difference between DV and DVCPRO25 is for PAL users: DVCPRO25 in PAL is 4:1:1, vs. DV in PAL which is 4:2:0.

In NTSC, DVCPRO25 and DV should be bit-for-bit identical. DV can be recorded to the tape drive (or P2 card or streamed), DVCPRO25 can only be recorded to a P2 card or streamed.

For 4:2:2 color sampling you have to go with DVCPRO50 or DVCPRO-HD. Neither of those can be recorded on the internal DV tape, of course, but they can be recorded to P2 or streamed out the firewire port.
 
Barry_Green said:
DVCPRO25 on tape is not an option with the HVX. DVCPRO25 is only applicable to P2 recording or firewire streaming. In those cases, the only difference between DV and DVCPRO25 is for PAL users: DVCPRO25 in PAL is 4:1:1, vs. DV in PAL which is 4:2:0.
Click to expand...

I thought that DVCPRO25 would be EXACTLY the same as DV when recorded to P2 (as in there is no tape to run at a different speed) and that by Panasonic mentioning DVCPRO25 I assumed it must be to tape. Why call it DVCPRO25 if it is recorded to P2, surely it is just DV then...?

Is it a slightly misleading marketing call by Pany, who do mention DVCPRO 25 on their website, or am I mistaken about something? I realise that the PAL DVCPRO25 and DV signals would be different, but why call it DVPRO25 in the US?

Thanks for correcting me Barry.
 
It is my understanding that a P2 recording of DVCPRO25 in NTSC would result in a bit-for-bit identical recording as a DV recording to P2. In PAL that's not true -- DVCPRO25 is different than DV, offering different color sampling. But in the US it should be identical. Unless there's something I'm missing...
 
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