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-   JVC GR-HD1U / JY-HD10U (https://www.dvinfo.net/forum/jvc-gr-hd1u-jy-hd10u/)
-   -   Chroma noise in the final analysis (https://www.dvinfo.net/forum/jvc-gr-hd1u-jy-hd10u/29481-chroma-noise-final-analysis.html)

Lynne Whelden July 23rd, 2004 05:30 AM

Chroma noise in the final analysis
 
Has anyone found chroma noise to be a significant problem? I remember seeing some posts early on and heard that some editing software was going to address it. But in the real world how does it translate? Is it only seen in certain colors like red? Is it only manifested in shadow areas? Is anybody really concerned about it to the point of being irritated by its presence? Will this always be a limitation of HDV or just of the JVC camera?

Troy Lamont July 28th, 2004 08:39 AM

Lynne,

I actually find the chroma noise (CN) more objectional than the edge enhancement that many others complain about.

CN is in about 80% of everything I shoot regardless of lighting. I was actually surprised to find it so prevelant in bright daylight shots, with and without filters.

Red isn't the only color it affects, almost all other bright colors are affected as well (green, blue, yellow). I just got back from Jamaica and while watching the footage I shot, it stood out like a sore thumb... :(

If I had one complaint, it would be the CN problem. I would think that the chipset has a lot to do with the chroma noise, so if the next gen of HDV camcorders have a different chip or even three chips, the CN would pretty much be eliminated.

Troy

Lynne Whelden July 28th, 2004 03:12 PM

hmmm
 
Thanks for letting me know...altho' it's curious that you're the ONLY one to respond to this. I wonder if the type of monitor one uses affects their perception of this problem? Has anyone tested their footage against different monitors or with a top-of-the-line broadcast quality monitor to come up with a benchmark? David Neuman created some software to deal with this issue. Any input from him on this subject?

Christopher C. Murphy July 28th, 2004 04:00 PM

Lynne, I have the CN too. But, I am trying to pretend my footage doesn't have it...otherwise, it's pretty annoying.

Overall, it's actually easy for me to pretend it isn't there because I'm so happy with the overall picture this thing makes.

Murph

Troy Lamont July 28th, 2004 04:09 PM

Lynne,

Not to disconcert your efforts, but I have a 55" HDTV that I spent close to $600 on getting professionally calibrated to the ISF standard.

CN also shows on my 17" PC display set to 1280X1024 res. This monitor was also calibrated professionally.

I've also had my camera connected to DLP sets, front projection sets and LCD panels both with component video and firewire connections, they all show the CN.

Troy

Lynne Whelden July 28th, 2004 08:18 PM

wow
 
So there you have it. It's there and it's a product (probably) of the first generation chips JVC uses. I guess the good news is there are software solutions to minimize it. And the next round of products will hopefully be cleaner. Thanks, everyone, for establishing that fact!

Mark Paschke July 28th, 2004 11:24 PM

The reds are very bad for sure, almost unwatchable.

Filtering makes this problem worse ( atleast using Cokin System) I have not noticed to much in the edge enhancement in the JY HD10u and I am seeing what I can do with Vegas 5 to help with chroma noise

Lynne Whelden July 29th, 2004 05:44 AM

wha...
 
Are you thinking that even the 10U has some edge enhancement? I thought it was just the HD1 that had that "problem."

Troy Lamont July 29th, 2004 11:03 AM

Edge enhancement...it's in there....
 
Here's JVCs official statement to that regard;

Quote:

There is some difference in picture quality, especially edge enhancement which has been balanced, shaped and reduced to match professional applications.
Troy

Ben Buie July 31st, 2004 10:04 PM

You do get chroma noise with this camera, that is for sure.

However, the good news is that there are fairly easy ways to get rid of it. We have had really good success using VirtualDub to remove the chroma noise. After we have rendered out our final product, we run it through VirtualDub and all is fine. VirtualDub will occasionally give us some small artifacts, but you can only see them if you know to look for them.

There is a free chroma noise plugin for VirtualDub that we use. We use that filter (with the "wide" settings) along with the Temporal Smoother set at level 2. The chroma noise filter gets rid of the color part of the noise, and the temporal smoother gets rid of the noise in general.

VirtualDub is pretty fast (a lot faster than going frame per frame in Photoshop). On our AthlonXP 2000 it cleans up our video at about 4 fps.

Another somewhat cool side-effect of using this filter combo; it gives any scenes with fast motion an EXTREMELY subtle motion-blur like effect.

If you have AspectHD (we don't, we have ConnectHD though), there is a free chroma-noise removal plugin for it as well. We have heard it works better than VirtualDub (basically the same results, but without any artifacts caused by the TemporalSmoother), but we are quite satisfied with VirtualDub for now (and we are pretty anal).

The bottom line is that we will NEVER go back to DV after using HDV. Sure, our lighting setups take more time, and we have to check every shot on a monitor, but the end result is the most filmic looking picture you can get for a camera under $50k.

Here are some quick tips to bring out the best in the HD10:

1) Use shutter-priority and lock the shutter at 1/60th. Force the exposure to be manual by using ND's. Keep several ND filters in your filter kit. We suggest (1) .3 ND filter and (3) .6 ND filters. That allows you to go up all the way to 1.8 ND (6 fstops!) in 1 fstop increments. We had to use all 6 fstops last week in the bright summer sun in order to get shallow DOF.

2) Avoid white clothing on your subjects. White is about the only color that reflects light enough to force the HD10 to change exposure in the middle of the scene.

3) Use a small color TV as your field monitor (if you can't afford better). We use a Toshiba 13" TV from Best Buy that was only $80.00. We picked it because of its light-weight (only 20 lbs), small size (only 12 - 14" along each dimension), and black tube (better contrast). A low-res color monitor is much better than a high-res B&W for this camera. It saved our butt last week when we forgot to white balance after switching from outdoors to indoors (on the LCD you couldn't tell, but everything was obviously red-cast on the TV).

Also, for people saying this camera is only good if you plan to output in HD, that is just not true. The truth is that there is no easier and cheaper way to output "Blockbuster-style" wide-screen DVD's. People with 4:3 TV's get a letter-boxed picture, and people with 16:9 TV's get a full-screen picture with better resolution than an SD picture that is stretched to fit the screen.

Anyway, if you have patience and want to go for a big-budget look on almost no-budget, the HD10 is the way to go.

We will be posting clips from our latest project very soon. It was a video press kit for this 17-year old girl trying to get a recording contract. It is a mix of music video, interview, and modeling style shots. It helps to have a subject who is very easy on the eyes :)

Regards,

Ben

Gabriele Sartori August 1st, 2004 12:06 AM

Ben, some help if you can
 
Ben

Could you describe how to get chroma noise reduction using the tools that you have? I've virtual dub and if I'm not wrong it takes a specific filter and a bit of skill to do what you are saying. Can you tell us a bit of "how to" and where download the filter if any?

Thank you very much
Gabriele

Christopher C. Murphy August 1st, 2004 05:01 AM

Ben, great tips....thanks for taking the time to post them!

Murph

Lynne Whelden August 1st, 2004 06:59 AM

refreshing!
 
Yes, it is NICE to hear such a positive and vigorously enthusiastic vote of confidence about the only camera on the HDV horizon for the next year at least!

Heath McKnight August 1st, 2004 02:22 PM

I have read, but not tried, that Lumiere HD and Aspect HD both have chroma noise reducers.

heath

Ben Buie August 3rd, 2004 05:53 PM

Here is the link to find the Chroma Noise filter we use with VirtualDub:

http://www.ifrance.com/freevcr/virtualdub/cnr-en.html

We check all the "wide" boxes when using the filter. We do not mess with any of the other settings.

In addition, we use Temporal Smoother set at Level 2 (the 3rd "tick" on the slider).

Most importantly, you must set your compression to Cineform under the Video menu.

Finally, choose "Save As" and it will generate the filtered .avi file.


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