Like I tried to explain earlier, the chroma resolution loss happens at the stage of compression to DV. This is just part of the DV format, that the chroma channel is downsampled. There's no way around that as long as you write to DV tape.

It's just the limitation of the DV format. And the HDCAM format for that matter. And although the XL2 may have slightly higher resolution chips resulting in a sharper image, the image that goes to tape still has it's chroma downsampled at the DV compression stage. This is what they mean by 4:1:1. For each 4 samples of luma information, only 1 sample of chroma is stored on the DV tape. So the only way around it is use a more expensive tape format, Digibeta or HDCAM SR - or start thinking about recording directly to disk...

Ideally you'd record 4:4:4 but that's a huge amount of data, so for practical reasons most digital formats use some kind of chroma downsampling.

Hope this helps.

Bar3nd

DVCPRO 50 is 4:2:2

Would using DVCAM tape instead of miniDV inprove the image quality?

Yes, and so is DigiBeta, albeit with a less harsh compression ratio and thus a higher bitrate.

But I fail to see how this adds to your point. The XL2 doesn't record to DVCPro50. And the 50 means that it's got a double datarate (50mbps) compared to DV25's 25mbps - it's essentially one of the more expensive tape formats that I was referring to in my previous post.

Recording to DVCAM instead of DV doesn't help either. The codec for DV and DVCAM is exactly the same. The most obvious differences are that DVCAM has a higher tapespeed so it's less prone to dropouts due to dirt on the tape. And DVCAM has locked audio.

Bar3nd

If you think it's possible to uprez a DV camera to HD, then I'm going to uprez my HD camera to be IMAX. ;-)
-Les

Uhm... did anyone say that?

Bar3nd

I said that - I think I can do a pretty darn good job of it once my scaling algorithm is working properly. (probably about 1 year's R&D away) I can already turn 4:1:1 DV into a pretty good facsimile of the original 4:4:4, which is the first step along the way of scaling DV to HD... OK - it will never be as good as shooting HD, but the better I can get it.....

Graeme

Uprezzing - some new test images
 

I've been doing some more work on the algorithm I was talking about earlier in this thread. Please don't get too excited as I'm still along way off a usable product, but I thought you'd like to see how it's progressing:

http://www.nattress.com/magic.htm

Comments (both positive and negative) are appreciated.

Graeme

I look forward, Mr. Nattress, to your results.

I also would like clarification on the use of Shake, though just finding the reference will make me research this question at Apple. The only thing I can add besides questions is the mentioned use of Photoshop. There is an excellent 'format' used for fractal image growth called GF Print Pro, now on version 5. While not as perfect as capturing the image at the resolution you would like originally, it's quite good. Designed for print media, it works with both RGB and CMYK. The extreme downside is the fact that even with macro automation, you're talking about frame by frame.

One note: What drew me to this thread was that I have EXISTING footage of a subject who is dead. I need to incorporate it with HD footage. Between the footage being shot and now, there have been a few changes in DV reality- What we now call High Definition becoming more common than Standard Definition. Many of the posts in this thread seem to be smugly declaring that shooting HD to start with keeps one from being an idiot.

Does anyone really believe that what we now know as HD will not be supplanted by higher resolution cameras, indeed, by 3-D, tank 3-D and even cameras shooting for hologram projection stages? Do you even today want to compare the highest DV HD with kodachrome? How about 4X5 kodachrome? It makes IMAX seem small. I do doubt, though, that anyone could think of a reason to transport 4X5 film for motion pictures.

Jeez, what a strange rant. Anyway, I'm looking, as the originator of this thread was, for a good way to upres.

Has anyone used this? I am fond of their Magic Bullet Editors and Look Suite, myself.

http://www.redgiantsoftware.com/instanthd.html