HD For Indies

Uh...Mike...Maybe I'm missing some context or simply confused by your statement, but *when* in the world would it be better to blow UP data??... I'd much rather capture original data at 1080 and throw data away (well, scale it down), than only have 720 at the capture stage and scale that up, effectively line-doubling and blurring the original. Please clarify what you're saying here. The CCD is only 720 lines but they're generating a 1080 image from that 720 acquisition?? Why is this good compared to having a CCD capture 1080 lines to begin with?
 

OK, Zane, think of it this way: Panasonic's $65000 Varicam has a similar resolution CCD (1280x720ish). BUT it subsamples before writing to tape, downsizing to 960x720. Loss of image clarity right there, on top of the drop from 10 bit to 8 bit and compression on top of that. IF it works as I suspect, and IF it writes out to this "bloated" format, it is NOT as efficient as a codec that actually recorded pixels (even after DCT compression) 1:1 to tape. By uprezzing, you're insuring that you've got (although distorted by the uprez) all the source info acquired (but compressed). Think of it this way - would you rather have 960x720 pixels to work (5.7 MB/sec @24p) with that started as 1280x720, or would you rather than 1280x1080 (11ish MB/sec @24p) that started at 1280x720?

Complain all you want about inefficient use of space, but I'd rather have more info to work with, even at twice the file size. It's not like hard drives are expensive or anything.

So it boils down to this - from a 1280x720 imager, I want as much valid, useful info as I can get off of it. If it means I'm being a bit inefficient, I'd rather have that than lost clarity/sharpness/information.

To address your point about starting at 1080 and throwing away data to end up at 720, that would be nice to have some super-sampling, but that's not an option with this camera. There is no starting at 1080, without spending 20 to 30 times as much on the camera. Sure, it'd be nice...got that much $$$ sitting around?

The Sony HDV claims an "effective" resolution of 1440x1080, which is what it writes to tape, but it has only 960x1080 pixels (the green is twice as wide, pushing effective resolution higher, but it's effectiveness varies depending on the colors you're shooting!)

Plus, Sony HDV is 4:2:0 and more heavily compressed in my test analysis so far.

The scene we shot in lighting good for F900 was too dim for Z1U, and color correcting the Z1U HDV footage quickly made artifacting all too visible.

So I think this'll be a very interesting camera for the money. The JVC should be interesting, too.

-mike
 

Ah...So you're basically gaining the storage bitrate of 11MB/s versus the 5.7MB/s... *that* is where you see the benefit. I can see that. Though you're still effectively getting a 720 image source, just leeching the higher bandwidth of the higher-res format. I think you'd probably have to really compare the artifacting involved to judge that one...but perhaps you're right and the bandwidth gain is higher than the resolution step up.

I didn't really get what you were comparing from your original post, though you compared the DVCPRO codec to the HDV one...but now I get it. Thanks for clarifying.

Clearly, when you start splitting hairs on the number of combinations of ways they can acquire/scale/compress/store HD, there's a lot of different variables involved, and less is sometimes more.
 

Aha...(further lightbulbs go off.) On reading your comment yet again I also see the obvious niceness of retaining the original horizontal resolution. Somehow that whole 960 scale fact escaped me in the original article as well. (Must review specs mentally before asking dumb questions next time.) I agree that your conjecture -- if correct -- sounds cool.
 

(MIKE) The other issue will be how to output this 1080p24 stuff - that isn't part of the DVCPROHD tape format as presently supported. New decks, or modifications to existing decks (unlikely), would be required to record DVCPROHD at 24fps 1080p.

Wonder if you have to add a 3:2 pulldown and record 1080i/59.94 to the decks?

The other big issue is on Final Cut Pro's side and BlackMagic's side. I haven't heard any support coming for DVCPROHD 1080/24p as a codec. BlackMagic is still having probelms with 720/24p footage.


- jeremiah black
 

(drool)

Would you care to speculate what this camera might cost?

By the way - sorry I didn't get a chance to talk to you after the SXSW panel. I'm the "Blogumentary" guy. :-)
 

I plan to buy one of these camcorders, and need to know which is best, and is there any better camcorder for the indie film-maker;

Panasonic AG-HVX200

JVC GY-HD100U

Sony HVR-V1U

Canon XL2