Masked Dead Pixels Show as Black Specs at DVinfo.net
DV Info Net

Go Back   DV Info Net > JVC ProHD & MPEG2 Camera Systems > JVC GY-HD Series Camera Systems
Register FAQ Today's Posts Buyer's Guides

JVC GY-HD Series Camera Systems
GY-HD 100 & 200 series ProHD HDV camcorders & decks.

Reply
 
Thread Tools Search this Thread
Old January 11th, 2007, 04:57 PM   #1
Major Player
 
Join Date: Feb 2006
Location: Houston
Posts: 789
Masked Dead Pixels Show as Black Specs

So, I just got my HD 100 back from JVC for warranty maintenance. I mentioned to them (through my dealer) in writing that I needed some dead pixels looked at. It looks like they ran the pixel masking routine to try to smooth them out. Only now when I see the uncompressed component output on my monitor I see about 15 or so black specs. I know that they're pixels because they flicker and are square. (Not dirt) Plus I can even see them without the lense attached.

So next, I ran the operation myself, about 8 times total and the specs are still there.

I've ran several 720/24 workflow tests to see if I could see the BLACK PIXELS when compressed into m2t, m2v, QT DNXHD 90 and DNXHD110 HDV, along with some tests in DV24p. The pixels due seem to get fainter with compression and I don't know if the average person would even notice once it goes to air or DVD. You can see them pretty good in m2v.

But, they are there . My question is that is this something I need to accept as a limitation of CCD technology or is this a problem that I need JVC to fix.

My camera is under warranty for 3 more weeks.

Thanks.
__________________
David Parks: DP/Editor: Jacobs Aerospace at NASA Johnson Space Center
https://www.youtube.com/user/JacobsESCG
David Parks is offline   Reply With Quote
Old January 11th, 2007, 05:44 PM   #2
Major Player
 
Join Date: Apr 2006
Location: Pacific NW
Posts: 431
I wonder if somehow the masking is not matching up with your black level values or gamma.
Mark Silva is offline   Reply With Quote
Old January 11th, 2007, 06:01 PM   #3
Major Player
 
Join Date: Feb 2006
Location: Houston
Posts: 789
Quote:
Originally Posted by Mark Silva
I wonder if somehow the masking is not matching up with your black level values or gamma.
Interesting theory.

If so do you think this is a calibration issue (JVC), firm ware, or user setting?
__________________
David Parks: DP/Editor: Jacobs Aerospace at NASA Johnson Space Center
https://www.youtube.com/user/JacobsESCG
David Parks is offline   Reply With Quote
Old January 11th, 2007, 07:48 PM   #4
Wrangler
 
Join Date: Aug 2005
Location: Toronto, ON, Canada
Posts: 3,637
David, could you please attach an exported TIFF or small m2t from one of your captures?

The pixel compensation system in the HD100 is supposed to clone or average the value of the pixels around it, not just make it black.

I wonder if your monitor might have some burnt out pixels?
__________________
Tim Dashwood
Tim Dashwood is offline   Reply With Quote
Old January 11th, 2007, 09:12 PM   #5
Trustee
 
Join Date: Apr 2005
Location: Chicago
Posts: 1,214
Quote:
Originally Posted by David Parks
So, I just got my HD 100 back from JVC for warranty maintenance. I mentioned to them (through my dealer) in writing that I needed some dead pixels looked at. It looks like they ran the pixel masking routine to try to smooth them out. Only now when I see the uncompressed component output on my monitor I see about 15 or so black specs. I know that they're pixels because they flicker and are square. (Not dirt) Plus I can even see them without the lense attached.

So next, I ran the operation myself, about 8 times total and the specs are still there.

I've ran several 720/24 workflow tests to see if I could see the BLACK PIXELS when compressed into m2t, m2v, QT DNXHD 90 and DNXHD110 HDV, along with some tests in DV24p. The pixels due seem to get fainter with compression and I don't know if the average person would even notice once it goes to air or DVD. You can see them pretty good in m2v.

But, they are there . My question is that is this something I need to accept as a limitation of CCD technology or is this a problem that I need JVC to fix.

My camera is under warranty for 3 more weeks.

Thanks.
I'd turn the camera right around and send it back in immediately.
Stephen L. Noe is offline   Reply With Quote
Old January 11th, 2007, 09:24 PM   #6
Major Player
 
Join Date: Feb 2006
Location: Houston
Posts: 789
Here's 4 tiff's from the original m2t. I purposely used out of focus shots so you can see that it is not part of the environment. Sorry I had to winzip because of site file limitations.
Attached Files
File Type: zip Pixelprob.zip (2.87 MB, 122 views)
__________________
David Parks: DP/Editor: Jacobs Aerospace at NASA Johnson Space Center
https://www.youtube.com/user/JacobsESCG
David Parks is offline   Reply With Quote
Old January 11th, 2007, 09:30 PM   #7
Major Player
 
Join Date: Feb 2006
Location: Houston
Posts: 789
Here are some shots exported out of Liquid (m2v) to tif.
Attached Files
File Type: zip Pixelprob2.zip (2.43 MB, 74 views)
__________________
David Parks: DP/Editor: Jacobs Aerospace at NASA Johnson Space Center
https://www.youtube.com/user/JacobsESCG
David Parks is offline   Reply With Quote
Old January 11th, 2007, 09:34 PM   #8
Major Player
 
Join Date: Feb 2006
Location: Houston
Posts: 789
2 more tif from m2v.
Attached Files
File Type: zip Pixelprob3.zip (2.43 MB, 73 views)
__________________
David Parks: DP/Editor: Jacobs Aerospace at NASA Johnson Space Center
https://www.youtube.com/user/JacobsESCG
David Parks is offline   Reply With Quote
Old January 11th, 2007, 09:39 PM   #9
Major Player
 
Join Date: Feb 2006
Location: Houston
Posts: 789
Tim or Stephen, If you get a chance, I hope you can glance at these. I know for a fact that it is not my monitor, and some of these pixels appeared as white dead pixels before. They seem to stand out against a solid background the most, like the blinds in the shot. By the way, these were viewed on a 1400x900 pixel 19inch Westinghouse, straight out of the camera, and within Avid Liquid full screen.

Thanks, Greatly appreciated.

ps, If these aren't funky pixels then I need to go to the eye doctor.
__________________
David Parks: DP/Editor: Jacobs Aerospace at NASA Johnson Space Center
https://www.youtube.com/user/JacobsESCG

Last edited by David Parks; January 11th, 2007 at 10:16 PM.
David Parks is offline   Reply With Quote
Old January 12th, 2007, 06:41 AM   #10
Trustee
 
Join Date: Apr 2005
Location: Chicago
Posts: 1,214
The only suggestion I could make to the issue is to try and run the pixel mask routine yourself and see if it's any better. If it's not then send the camera back in. Your images show ALOT of specks all over the place.

Another thing to try is to put your camera's shutter speed to a low number. Do you have specks all over the screen? Put your lens cap on, do you have specks all over the scene?
Attached Thumbnails
Masked Dead Pixels Show as Black Specs-pixelprob5.jpg  
Stephen L. Noe is offline   Reply With Quote
Old January 12th, 2007, 08:02 AM   #11
Major Player
 
Join Date: Apr 2004
Location: Kelowna BC Canada
Posts: 706
Any chance that it's dust on the sensor?
__________________
www.ascentfilms.com
Jiri Bakala is offline   Reply With Quote
Old January 12th, 2007, 09:26 AM   #12
Major Player
 
Join Date: Feb 2006
Location: Houston
Posts: 789
Thanks, Stephen for looking at the tiff's. I lowered the shutter to 1/6th and man, tons of white pixels show up. It looks like a hail storm. With and without the lens and lens cap.

I'm a little worried that JVC won't do anything, my dealer knows nothing about this camera and they're not authorized to even touch it.

Since this has already been to JVC once is there someone within JVC that could look at this?

Not much time left on the warranty.

Thanks.
__________________
David Parks: DP/Editor: Jacobs Aerospace at NASA Johnson Space Center
https://www.youtube.com/user/JacobsESCG
David Parks is offline   Reply With Quote
Old January 13th, 2007, 10:50 AM   #13
Wrangler
 
Join Date: Aug 2005
Location: Toronto, ON, Canada
Posts: 3,637
David,

It looks like Carl Hicks is your district rep, but he hasn't posted here since Monday so he's probably busy at CES and hasn't read this thread.

Here's his contact info as posted on the JVC Site.

http://pro.jvc.com/prof/attributes/d...&zipcode=77001

If you can't reach Carl on Monday, try calling 1-800-582-5825 tech support and find out what your next step should be.
__________________
Tim Dashwood
Tim Dashwood is offline   Reply With Quote
Old January 13th, 2007, 01:23 PM   #14
Major Player
 
Join Date: Feb 2006
Location: Houston
Posts: 789
Thanks Tim, much appreciated.

Cheers.
__________________
David Parks: DP/Editor: Jacobs Aerospace at NASA Johnson Space Center
https://www.youtube.com/user/JacobsESCG
David Parks is offline   Reply With Quote
Old January 13th, 2007, 03:05 PM   #15
 
Join Date: Sep 2005
Location: Austin, Texas
Posts: 289
CES is for consumer products.
you can probably reach Carl Hicks on Monday. He's pretty good and making himself available.
You can also contact the JVC sales engineer, Rob Yaroush, listed on the previous link and discuss your situation.
Terry Nixon is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

B&H Photo Video
(866) 521-7381
New York, NY USA

Scan Computers Int. Ltd.
+44 0871-472-4747
Bolton, Lancashire UK


DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > JVC ProHD & MPEG2 Camera Systems > JVC GY-HD Series Camera Systems


 



All times are GMT -6. The time now is 04:43 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network