HD200 compared to XL-H1 or HVX-200?

[Carl Hicks]

Originally Posted by Garrison Hayes

Well You have to Realize That the HVX200 Records uncompressed HD video... on a totally different format (P2)...the XL H1 doesnt... and it's DV or HDV

Hi Garrison,

The HVX200's DVCProHD mode is far from uncompressed. (This is a common misconception) It uses 100 Megabits/Sec DV-based compression. See this quote from Wikipedia:



http://en.wikipedia.org/wiki/DVCPRO_HD

"DVCPRO HD, also known as DVCPRO100, uses four parallel codecs and a coded video bitrate of approximately 100 Mbit/s, depending on the format flavour. DVCPRO HD is also 4:2:2. DVCPRO HD downsamples native 720p/1080i signals to a lower resolution. 720p is downsampled from 1280x720 to 960x720, and 1080i is downsampled from 1920x1080 to 1280x1080 for 59.94i and 1440x1080 for 50i. This is a common technique, utilized in most tape-based HD formats such as HDCam and HDV. Compression ratio is approximately 6.8:1."



HDV1 from JVC does not require downsampling from 1280 x 720 to 960x720. HDV1 records the full 1280x720 frame, and it uses MPEG-2 compression instead of DV compression.


NO camcorder format currently available can record uncompressed HD that I am aware of.

[Jemore Santos]

It's not uncompressed HD in the HVX it uses DVCproHD which is an intraframe codec.

[Pete Bauer]

Originally Posted by Garrison Hayes

...the XL H1 doesnt... and it's DV or HDV

Clarification: Carl is correct that none of these cameras record onboard uncompressed video, since the HD-SDI data rate and storage requirements are huge. However, more and more "affordable" cameras, including the XL H1, do output uncompressed 1080i60.

[Stephan Ahonen]

I doubt there's a way to physically move tape fast enough to record a full bandwidth HDSDI stream. HDCAM SR comes close at 880 kbps, but an HDCAM SR tape is bigger than an HD100. Literally.

[Ken Hodson]

Carl it is true that DVCproHD can capture at 100 Megabits/Sec but that is a best case senario. Most shooters due to P2 limited storage or the nature of the type of shooter who would buy a cam like that will likely shoot at 24p. In that case DVCproHD is a mere 40 Megabits/Sec. When you consider how much more efficient HDV is over DVCproHD I don't believe it holds any advantage at all. Which is proof when comparing footage between the cams.
The misconception that it shoots uncompressed is truly hilarious. I wonder how people get these ideas?

[Carl Hicks]

Originally Posted by Ken Hodson

Carl it is true that DVCproHD can capture at 100 Megabits/Sec but that is a best case senario. Most shooters due to P2 limited storage or the nature of the type of shooter who would buy a cam like that will likely shoot at 24p. In that case DVCproHD is a mere 40 Megabits/Sec. When you consider how much more efficient HDV is over DVCproHD I don't believe it holds any advantage at all. Which is proof when comparing footage between the cams.
The misconception that it (DVCPro HD) shoots uncompressed is truly hilarious. I wonder how people get these ideas?

I wonder the same thing. I have run across several people who think that DVCPro HD and even HDCam are uncompressed. Some people need to be educated in this regard.

[Carl Hicks]

Originally Posted by Stephan Ahonen

I doubt there's a way to physically move tape fast enough to record a full bandwidth HDSDI stream. HDCAM SR comes close at 880 kbps, but an HDCAM SR tape is bigger than an HD100. Literally.

With full res uncompressed HD requiring 1.5 Gb/Sec, it will be a LONG time before on-board uncompressed HD is a reality, if ever.

[Stephan Ahonen]

Originally Posted by Carl Hicks

With full res uncompressed HD requiring 1.5 Gb/Sec, it will be a LONG time before on-board uncompressed HD is a reality, if ever.

Well, never say never, but I'll bet when it does it will be a hard disk system like XDCAM rather than a tape format. Maybe it'll be a flash memory system a-la-P2, but prices on flash memory will have to go WAAAAY down before that goes mainstrem.

[Werner Wesp]

Originally Posted by Carl Hicks

With full res uncompressed HD requiring 1.5 Gb/Sec, it will be a LONG time before on-board uncompressed HD is a reality, if ever.

No, we just have to go back to wider tapes. e.g. bring back VHS-C tapes with ME density of data like miniDVtapes and make it run a few times faster... That would open up a whole world of possibilities. Perhaps no uncompressed straight away, but something like Cinform codec?

[Ken Hodson]

Exactly, a lossless compressed codec is a far better idea. The only hold back for that is a lot of processing power.

[Antony Michael Wilson]

Actually, there are already HD camera systems out there that will capture uncompressed HD to flash memory. For examply, the Grass Valley Viper can record uncompressed RGB 4:4:4 2K to the Venom FlashPak or FlashMag in the Arri version. The Dalsa Origin can capture to a chip capable of 4K uncompressed. However, this is in a whole new league and warrants no comparison to DVCProHD or HDV, of course. I'm not sure of the cost of a single Venom FlashPak memory unit but I'll bet it's equivalent to several HVX200 cameras.

DVCProHD does have key advantages over HDV, which have been discussed at length here many times but it is a long, long way from being an uncompressed system and - in the grand scheme of things - DVCPro HD users would be misguided to direct any snobbery towards those acquiring HDV1 on the JVC cameras because the DVCProHD advantages are off-set by many factors, including some which Carl has already mentioned.

As Carl mentions, standard HDCAM (not SR) is significantly inferior to uncompressed.

[Jack Walker]

The film "The Russian Ark" was shot in 4:4:4 uncompressed video. A special hard drive system was put together in Germany for the film, allowing the recording of the entire film (one take) on the disks.

Here is a short article about the film:
http://www.sptimes.ru/index.php?acti...&story_id=6203

The camera used was the Sony HDW-F900. There are articles somewhere that cover in detail the technical aspects of shooting the film.

The film is found in the IMDB as "Russkiy kovcheg":
http://www.imdb.com/title/tt0318034/

[Werner Wesp]

I always wonder why people want to campture uncompressed HD from camera's like the HVX or that price range. The performance of the encoder should match the performance of the camerahead - more so, I'd choose a better camera head over a better recording format any day: I'd rather shoot with a GY-HD100 and record it on S-VHS, rather then shooting with cell phone camcorder and capture it as uncompressed video.

Anyhow, what people need to understand is that the encoders match the performance of the heads. I've told this before: 40 Mbps for DVCPROHD is not a lot better then 20 - 25 Mbps for HDV, since the first codec needs to compress any frame by itself, where the second codec re-uses information of previous frames, i.e. the HDV codec is therefor a lot more efficient. Look at it like this: DV is also 25 Mbps compression, but each frame by itself. If you render that to an MPEG2-stream (which encodes GOPs) of 8 (!) Mbps you can get quality that is virtually the same for less then 1/3 of the data. Rendering it to 12 or 13 Mbps (1/2 of the data) would make a perfect match, perhaps it would even be bandwith overkill. Consider that when comparing DVCPROHD and HDV.

There's more (obviously) that makes it more complicated, but this is still the way to look at it in general terms. But to be fully correct you should consider that the resolution of DVCPRO is lower. That is a disadvantage in itself, but the encoder has less raw data to encode, which obviously enhances the performance of the codec. Personally I think this is an advantage for HDV/ProHD, because I don't like the upsampling in resolution. Furthermore, since it is framebased, DVCPROHD is easier to edit and to work with in general. HDV/ProHD needs an intermediate codec or it handles somewhat difficult. MPEG2 streams aren't performing well under re-encoding as well: multiple generation MPEG2 is a thing to avoid at all times (with intermediate codecs etc...)

[Antony Michael Wilson]

Originally Posted by Werner Wesp

I always wonder why people want to campture uncompressed HD from camera's like the HVX or that price range. The performance of the encoder should match the performance of the camerahead - more so, I'd choose a better camera head over a better recording format any day: I'd rather shoot with a GY-HD100 and record it on S-VHS, rather then shooting with cell phone camcorder and capture it as uncompressed video.

This is an extremely important point. Those using camera systems like the Venom are shooting to extremely high standards with huge amounts of money. The camera head and lenses those guys are using are so superior to the HVX or the HD100 series that there is little room for comparison. What I particularly like about the HD100 is that there is a sense of proportion to the whole thing. Okay, the stock lens is not so great, HDV has major limitations but the cost/performance relationship is simply amazing and all the components match each other well in terms of cost/performance. JVC don't have Panasonic's need to hamstring the low-end camcorders to protect the high-end stuff, so we get things like interchangeable lenses and pro manual control, shoulder-mount form factor etc. Okay, HDV has technical limitations but you can still create excellent pictures with it and I'd go so far as to say that many of us would not have the skills to do much better with an uncompressed D-cinema rig. As to DVCProHD, I agree that the lower resolution is a shame and that it does off-set HDV's interframe disadvantage and bit-rate to some extent but the difference in the pictures between HDV and DVCProHD is usually just academic. Nearly all the great DVCProHD footage I have seen was shot on a Varicam - far better camera, far better lens and far better operator than some of us lot!

[Thomas Smet]

Originally Posted by Werner Wesp

I always wonder why people want to campture uncompressed HD from camera's like the HVX or that price range. The performance of the encoder should match the performance of the camerahead

In terms of raw image that may be true but the camera head is always better. I have worked with footage from even a HC1 where it was captured live uncompressed and as a test compared the HDV tape recorded at the same time and there was a huge difference. In a perfect setup yes HDV can look good but the real world is hardly ever perfect. I find even with using component that the uncompressed is much cleaner, has less artifacts, less banding and blocking in gradients, and finally 4:2:2 color compared to 4:2:0. With interlaced HDV the 4:2:0 is even worse.

As for DV encoded to mpeg2. It is far from perfect. A DVD encoded at 8 mbits will not look exactly the same as the DV version. Perhaps if the camera is looked down that may be the case but as soon as you add a complex scene and lots of movement the 25 mbit DV version will look much better.

HDV is basically like the DVD version of HD. It floats somewhere around like what a DVD would look like with a bitrate of 5-6 mbits. 720p HDV seems to be around what a DVD would look like with a bitrate around 7 mbits.

So uncompressed is a lot better to work with and may not be a lot better in terms of raw image detail but it can make a big difference for effects work.

I have also worked with some HDCAM footage from a blue screen shoot and I can tell you that the HDCAM format doesn't even come close to what the camera can do. HDCAM is like a really bad form of DV but at a higher resolution. It may be one of the best tape formats out there right now (huge debate on this one) but I would gladly take uncompressed from a F900 any day over HDCAM tape.