"Grid" look when shooting in DV mode at DVinfo.net

Go Back   DV Info Net > JVC ProHD & MPEG2 Camera Systems > JVC GY-HD Series Camera Systems

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


Reply
 
Thread Tools Search this Thread
Old July 29th, 2009, 09:58 AM   #1
Trustee
 
Join Date: Jul 2005
Location: Willmar, MN
Posts: 1,400
"Grid" look when shooting in DV mode

I just shot some footage yesterday with my HD100U in DV mode. When I started working on it today I noticed a blocky grid type look to most of the footage. It's hard to see on still images, but here's a good example:

Full size:
http://www.famousdavispro.com/images/badhat.jpg

Detail:
http://www.famousdavispro.com/images/badhatdetail.jpg

Now it's only more noticeable on the red hat, but it appears to be on all the footage, regardless of subject. Is this a problem with the camera, the lens, the tape stock (Sony DVM60), or what?
Chris Davis is offline   Reply With Quote
Old July 29th, 2009, 10:20 AM   #2
Inner Circle
 
Join Date: Nov 2006
Location: Tallahassee, FL
Posts: 4,100
It's a problem with shooting DV, and even more a problem with you over saturating the colors in DV.
__________________
DVX100, PMW-EX1, Canon 550D, FigRig, Dell Octocore, Avid MC4/5, MB Looks, RedCineX, Matrox MX02 mini, GTech RAID, Edirol R-4, Senn. G2 Evo, Countryman, Moles and Lowels.
Perrone Ford is offline   Reply With Quote
Old July 29th, 2009, 02:39 PM   #3
Wrangler
 
Join Date: Aug 2005
Location: Toronto, ON, Canada
Posts: 3,637
4:1:1 chroma subsampling is used with DV. It basically means that your luminance is 720x480, but your chroma sampling is 180 x 480. (Can someone please check my math.)
__________________
Tim Dashwood
Tim Dashwood is offline   Reply With Quote
Old July 29th, 2009, 06:38 PM   #4
Inner Circle
 
Join Date: Sep 2002
Location: Vancouver, British Columbia (formerly Winnipeg, Manitoba) Canada
Posts: 4,087
Tim is right and his math is good.

And so is Perrone.
__________________
Shaun C. Roemich Road Dog Media - Vancouver, BC - Videographer - Webcaster
www.roaddogmedia.ca Blog: http://roaddogmedia.wordpress.com/
Shaun Roemich is offline   Reply With Quote
Old August 4th, 2009, 03:58 PM   #5
Major Player
 
Join Date: Nov 2005
Location: Belgium
Posts: 695
I never shoot in DV, unless the client wants DV tapes to take with him at the location.
I prefer to shoot in HD, Edit in HD and only after the final edit, only then to convert to what is needed to preserve the highest quality at the end.
Computers now-a-days can handle the HD pretty good as if you are editing DV years ago on a Pentium.
__________________
Marc Colemont - Belgium - http://www.mc-productions.be
JVC GY-HM850's, HM890, HM600
Marc Colemont is offline   Reply With Quote
Old August 4th, 2009, 11:14 PM   #6
Trustee
 
Join Date: Feb 2006
Location: USA
Posts: 1,684
That doesn't look like normal DV artifacting to me. It looks much worse. I don't know this camera so it is possible that it is not optimized for SD. That is the case for example with the HVX200 which has awful stair step aliasing in SD, much worse than a DVX100.
Whatever the cause, it is not acceptable DV in my opinion though.
Leonard Levy is offline   Reply With Quote
Old August 5th, 2009, 09:44 AM   #7
Wrangler
 
Join Date: Aug 2005
Location: Toronto, ON, Canada
Posts: 3,637
That's actually pretty normal looking DV encoding for an edge of pure red or pure blue. It would look the same with the DVX100.
__________________
Tim Dashwood
Tim Dashwood 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...

Professional Video
(800) 833-4801
Portland, OR

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

Z.G.C.
(973) 335-4460
Mountain Lakes, NJ

Abel Cine Tech
(888) 700-4416
N.Y. NY & L.A. CA

Precision Camera
(800) 677-1023
Austin, TX

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

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 01:31 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2017 The Digital Video Information Network