Can capture card improve HDV tapes for broadcast?
by Steve Skemp
on
Feb 7, 2008 at 10:46:32 pm
I originally posted about "smoothing out color gradients" in Vegas, but now have a broader topic to address. I've been shooting to HDV tapes for a while and creating HD videos in .wmv format.
However, I now have requests to deliver videos that will be shown on broadcast systems - which I haven't done before. My first project is to export put to SD PAL in an uncoded Quicktime file. (The client will encode the video for broadcast.)
Now that I export to PAL or other formats, I get the "banding" or "contouring" color effect with backgrounds, most visibly with the sky. Douglas Spotted Eagle mentioned this was a constraining effect of 8-bit HDV video. I've adjusted the project properties to 32-floating bit, which improves the picture somewhat. (Side question, why don't I see this effect when I play HDV tape straight from my Z1U camera to LCD HDTV monitor? The image quality is beautiful then.)
My question is how I can set up my workflow on a limited budget to deliver the best HDV footage for new broadcast clients? My first look is to buy a quality capture card, but I'm confused about some of the claims. BlackMagic claims its Intensity Pro can take HDV and remove the "contouring" problems using its capture card by delivering uncompressed broadcast-quality HD video. Can it really do that with recorded HDV tape and solve my problem? Or am I stuck with my footage using the HDV format. Specifically, I shoot with the Z1U, but don't know if Intensity Pro works with my camera. I'm thniking about changing to the XDCam format soon.
I can't find customer support at BlackMagic's web site, so I'm back here. I'm want to eliminate the "contouring" problem, but also figure out what steps I should take to enhance generally the HDV video I deliver for broadcast, both with captured tape footage and projects in the future.
~You're looking at the color before you're pushing the saturation. Pushing the saturation as you indicated you're doing, is pushing the limits of 8 bit when it's highly compressed (or not, sometimes)
~you may not be shooting correct exposure when shooting the sky, it may be that you're trying to cram too much dynamic range into the shot. Consider a grad if the foreground is properly exposed.
A capture card will allow you to capture 10bit, and maybe your system is fast enough to manage 10 bit uncompressed, maybe not. Using the 32 bit 1.0 linear scale in Vegas, you are also working with a large bit range, which is why you can push saturation much harder. You can also blow beyond dynamic range, too. Kinda like adding too much bass and too much high end to audio, it becomes mushy and brittle.
I use the AJA Xena card, it's my preference. Black Magic used to work great in Vegas, but the drivers are like playing "Whack-a-mole" so for the time being, I'm using Xena. Hoping to see the Intensity completely supported with drivers for Vegas soon; for the cost, the Intensity is the sweetest product I've seen in it's niche.
Douglas Spotted Eagle
VASST
Certified Sony Vegas Trainer
Aerial Camera/Instructor
Re: Can capture card improve HDV tapes for broadcast? by Michael Palmer on Feb 8, 2008 at 1:43:56 am
"I can't find customer support at BlackMagic's web site, so I'm back here."
DSE has said AJA is makes a great capture card and I want you to know AJA has wonderful support team that stands behind every card/product they make. There are plenty of low cost ways to transcode HDV to an intermediate codec for both PC and Mac, AJA is a great choice for both capturing and monitoring.
Re: Can capture card improve HDV tapes for broadcast? by Michael Palmer on Feb 8, 2008 at 1:44:39 am
"I can't find customer support at BlackMagic's web site, so I'm back here."
DSE has said AJA is makes a great capture card and I want you to know AJA has wonderful support team that stands behind every card/product they make. There are plenty of low cost ways to transcode HDV to an intermediate codec for both PC and Mac, AJA is a great choice for both capturing and monitoring.
Re: Can capture card improve HDV tapes for broadcast? by Uli Plank on Feb 8, 2008 at 8:53:57 am
Sorry, but no capture card will improve on that problem, since it's inherent to HDV compression, and that's on tape! Once the color information is lost, it's lost.
The only exception: capturing live from the camera into the computer, since most HDV camcorders can deliver an uncompressed live feed. But since you are talking about skies, I'm afraid it's not a viable solution for you to drag a computer with a capture card to location.
Of course you should not continue to work in HDV once you start tuning your colors. On the Mac ProRes is the answer (a recent article here on the Cow desribes how to get from HDV to ProRes via FireWire – no card needed). On the PC, Cineform should be as good.
As already mentioned, a grad filter might help to some degree. Plus, adding a very small amount of noise to the image before final output can mask it to some degree.
Regards,
Uli
Director of the Institute of Media Research (IMF) at Braunschweig University of Arts
Re: Can capture card improve HDV tapes for broadcast? by Steve Skemp on Feb 8, 2008 at 3:11:48 pm
Thanks for the responses. Uli, I caught on to your brief mention of Cineform. I had just checked their website and they make claims of solving the color banding problem, even with archived HDV footage. Can anyone attest to that? And which product should I use - don't want to overpay for Prospect HD unless that is the one flavor that will deliver results.
Re: Can capture card improve HDV tapes for broadcast? by Douglas Spotted Eagle on Feb 8, 2008 at 4:36:24 pm
Sorry, but no capture card will improve on that problem, since it's inherent to HDV compression, and that's on tape! Once the color information is lost, it's lost.
Not quite so.
Yes, the information is lost, but how that loss is managed will vary with workflows. For example, high-compression 8bit data can be improved by capturing via component 10 bit, as there is chroma processing that takes place on capture.
Additionally, embedding the 8bit data in a 32bit project (depending on how the NLE functions) can make a significant difference.
It's worth it for the FCS workflow guys to pull their heads out of the apple from time to time to see how other systems work, what they bring to the table, and why there're good tools to have in addition to the tools Apple puts on the table. The world doesn't revolve around ProRes any more than it revolves around 22:11:11 being the "grail." :-)
Douglas Spotted Eagle
VASST
Certified Sony Vegas Trainer
Aerial Camera/Instructor
Re: Can capture card improve HDV tapes for broadcast? by Uli Plank on Feb 8, 2008 at 4:54:13 pm
OK, yes, maybe that was a bit too negative. Even on a Mac ;-) you can improve color information with filters like the excellent ones from Graeme Nattress' – but don't expect miracles, HDV will always be a heavy compression.
Regards,
Uli
Director of the Institute of Media Research (IMF) at Braunschweig University of Arts
Re: Can capture card improve HDV tapes for broadcast? by Tim Kolb on Feb 9, 2008 at 3:19:40 pm
[Douglas Spotted Eagle]"...how that loss is managed will vary with workflows. For example, high-compression 8bit data can be improved by capturing via component 10 bit, as there is chroma processing that takes place on capture.
Additionally, embedding the 8bit data in a 32bit project (depending on how the NLE functions) can make a significant difference."
I have to say I agree completely.
[Douglas Spotted Eagle]"It's worth it for the FCS workflow guys to pull their heads out of the apple from time to time to see how other systems work, what they bring to the table, and why there're good tools to have in addition to the tools Apple puts on the table."
I absolutely, positively agree with that statement...
FCP is the absolute KING of DVC Pro 50, 100 native editing...but HDV has many different but competent approaches.
