Truth or Snake Oil?

T

tcgliderguy

Member
I'm considering buying an XH-A1...... I love the image quality that I am seeing on sample clips posted on various forums, etc., but I am concerned about the limitations of HDV... particularly when it comes to keying, etc. I've always thought that HDV used 4:20:0 color sampling....

But now I read on Canon's website about their DIGIC DV II signal processor as copied and pasted below....

>DIGIC DV II is the next generation of Canon's exclusive DIGIC DV signal processing technology. DIGIC DV II processes the HD signal at 1440 x 1080 with 4:2:2 color sampling. Designed specifically for processing the immense volume of information in 1080 HD signals, DIGIC DV II ensures optimal image quality for HD video.<

Does the XH-A1 truly have 4:2:2 ... or is this just marketing department snake oil?

Thanks!

-Taylor
 
>Internal processing is done at 4:2:2. But the HDV recording media only supports 4:2:0.<

So is there a way to record at 4:2:2..... coming out of the component outputs.... to a Firestore, deck, etc?......

Thanks for the info.....

-Taylor
 
You can record 4:2:2 via the component output but you will need a heafty array to capture it. In all honesty, 1080P HDV from the A1 does holds up remarkably well in post production, and when shooting greenscreen I have seen some beautiful keys come from HDV footage.
What are you looking to do with the camera? Are you looking to only shoot greenscreen?
 
>All these great footage examples say the same basic thing: the camera just works.<

Thanks for the input guys! Since my I first posted the question, I've been doing some digging around the web, and found another interesting possibility.....

Dan and Don Berube, in Boston, are writing great things about the Convergent Design HD-Connect SI box.... which will translate the Firewire output from a deck (or the XH-A1 directly) into an HD-SDI stream.... that can be edited in a DVC Pro timeline in Final Cut.

That would put the whole investment... for the XH-A1, a Sony HVR-M15U deck, the Convergent Design box, and an AJA IO-LD capture card, to about $7650.

To me, that looks like the best of both worlds..... 4:2:2 editing... and less $$$$$ spent than just an HVX-100 .....

Comments?

-Taylor
 
I have an XL-H1 SDI 4:2:2 clip in photojpeg QT format at dvinfo.net. Link: http://www.dvinfo.net/conf/showthread.php?t=77993

This was a test to see how the camera handled skin tones with 4:2:2. What I found from the HDV tape was similar quality, but this will give you an idea of what the A1 can do from the analog port. (same basic imaging in both cams) Play around with contrast and saturation in QT player and you'll see how it can pop. :)
 
I am going to go right ahead and say it... the disadvantages of the HDV codec are widely exaggerated by some companies. The fact of the matter is in 99% of shooting situations no one can tell the difference.

In 24f the amount of temporal information the XH is writing to tape is so much less than the 60i HDV was designed for, that motion artifacts are almost non-existant.

Also, you have to remember that the XH has substantially higher recorded resolution than the any of the competitors, which means the 4:2:0 color sampling is being pulled from a higher resolution base image... further negating any downside to 4:2:0!

This post will probably get deleted, but i though i would give my 2 cents anyway!
 
In my situation, the Black Magic Extreme card would be nice.... but I would have to upgrade my dual G5 Mac to a Mac Pro to have the PCIe compatibility.....

Gilda Radner was right..... "It's ALWAYS something..... " :-(

-TC
 
Elton,

If I can ask for a subjective opinion.... do you think that the Kona LH would make up for the performance hit of switching from DV to HDV?

In other words.... would I edit and render at about the same speed that I am now.... with a straight DV/Firewire setup?

-TC
 
The Kona helps a lot, but the main performance hit is the unavoidable "conform to HDV" process which is fairly render intensive if you want to print back to tape. It takes my machine typically about 3x the running time of a piece to render before output. Meaning--a 20 min. timeline without a ton of fx other than CC and simple transitions takes about an hour to render. If the edit is mostly cuts and simple transitions, the output time is much shorter.

Where the card does make up for that hit is giving you the ability to capture to other codecs in realtime. DVCPRO HD edits about the same as DV (if you have a fast, large hard drive) with a Kona card on a G5. And I can't tell you how valuable it is to be able to live scrub your timeline to an HD monitor, rather than having desktop cinema preview mode as your sole method of full screen monitoring.

The Kona opens up all sorts of possbilities, but in general the HDV acceleration helps mostly with real time previews. It doesn't help with final renders and output to tape.

Your money might be better spent selling the G5 and upgrading to a MacPro. When you need an HD card, get the Blackmagic Extreme HD.
 
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