[loki74]

I am thinking of getting either a Canon XL2 or a JVC GYHD-100U. Both look good to me, but I would like to have the HD cam. Unfortunately, it uses HDV = big time compression = hard to do some post production stuff. Assuming I was able to get together TONS of space... would it be possible to uncompress HD footage captured to Long-GOP MPEG2 and edit/fiddle with it uncompressed, making post production stuff a whole lot easier? Or even if I could uncompress it to just a lower level of compression?

From what I hear, the Long-GOP MPEG2 is hard to color correct and stuff. I may or may not do chroma keyng, so ability to manipulate footage is vital...

PS I am using Final Cut Studio HD.

[k_munic]

hi loki,

importing "HD" footage with any HD app of Apple (iM or FC) uses the "Apple Intermediate" codec. it converts the mpeg2 material into "something" which is editable with frame aaccuracy… (no long-GOP).

AI has a very high quality.

because both apps are "HD" (which is not 720/1080 i/p) ready, you don't "feel" any difference…

[loki74]

interesting... so does that mean that chroma keying, matte extration, color correction blah blah blah be just as easy as oh, say, DV when using Apple Intermediate? (That would be very cool)

btw what do you mean by HD (not 720/1080 i/p)? ...Are not 720p, 1080i, and 1080p, the current HD standards? Although I did read somewhere that they dont meet ATSC standards for HD or something like that...

[dlefebvre]

HDV is not 1920x1080 but 1440x1080. Losing horizontal resolution is way less dramatic than losing vertical resolution.

[k_munic]

what lefebvre said is a 100% correct… what we get offered by Sony & Co plus "Steve's year of HD" is NOT what real HDTV is… "HD" has less horizontal res, by playback it gets interpolated to get the full res…

to my knwoledge, FCPro is able to do all that stuff you mentioned (color correction etc) with "HD" material… but, in detail, you should ask in specialized forums for final cut pro (sorry, no link, I just know a german one )

[dlefebvre]

You'll be able to do everything with HDV in FCPro (v.5). HDV like DV is not the ideal color space for full control color correction, but you'll be able to get good result on basic adjusment and might even be able to some creative color treament. You just have to be sure your footage is perfectly shot. HDV and DV footage is very tough to work with when it's under or overexposed. It's true for every format but on this level, DV and HDV are the worst.

Here is a basic video format and color space explaination. A component video signal is made of 3 components : Luminance (Y), Luminance minus Red (Y-b), Luminance minus Blue (Y-b). That translate to 3 digits in digital format. By reducing the number of color samples you can efficiently reduce the amount of data required for video. The cost is less color definition. You probably won't notice it if you look at the original source but you have less latitude to modify the source with color correction.

HD
Full uncompressed dual link HD is 4:4:4 (4 Y samples: 4 Y-r samples: 4 y-b samples) at 1.4 Gbits/sec.
D5 HD is 4:2:2 at 270 Mbits/sec
HDCAM is 4:2:2 at 144 Mbits/sec
DVCPro HD is 4:2:2 at 100 Mbits/sec
HDV is 4:2:0 Mpeg-2 at 25 Mbits/sec for 1080i and 19.4 Mbits/sec for 720p

SD
Full uncompresed SD is 4:2:2 at 270Mbits/sec
Digital Betacam is 4:2:2 at 70 Mbits/sec
DVCPro 50 is 4:2:2 at 50 Mbits/sec
DVCPro is 4:2:2 at 25 Mbits/sec
DVCAM and DV is 4:2:0 at 25 Mbits/sec

[loki74]

Damn I wish I could afford a Panavision Genesis or a Viper or something like that. grr.

(edit:misread post, question answered) ..is there ANY way I get get true HD or SD uncompressed?

[dlefebvre]

There's a few good uncompressed HD cards out there (Kona 2, DeckLink HD). Both card support Dual link 4:4:4 HD input. There not really uncompressed but used lossless compression schemes. Be aware that uncompressed HD takes about 9 GB/min. But you also need a good source. You can shoot in HDV and capture in umcompressed HD trough the Components output of the camera, but's it's still an HDV source. You will be in a format that allows you more latitude for treatment but you won't have more information than the original source can provide. In high end formats there is also some limitations. Even though it's a HD broacast format, HDCAM compressed the signal on the tape (144 Mbits/ec as opposed to the 1.4 Gbits/sec of trully uncompressed HD).
Uncompressed HD requires lot of processing power, extremly fast drives and expensive equipment. So the best way to get fully uncompressed HD is to win big at the lottery.