AE/Keylight/HVX noise problem at

Go Back   DV Info Net > Cross-Platform Post Production Solutions > Digital Compositing and Effects

Digital Compositing and Effects
After Effects, Shake and everything else.

Thread Tools Search this Thread
Old October 11th, 2006, 12:39 PM   #1
New Boot
Join Date: Jan 2006
Posts: 18
AE/Keylight/HVX noise problem

Aha, the dreaded HVX noise problem rears its head at last. Currently I've been hired to fix some truly awful greenscreen keys that came from HVX200 footage. I've shot greenscreen on the HVX myself, and it's been more than fine, so obviously there's something wrong with the footage to start. Anyway, after quite a bit of effort, I've been able to get decent keys. The problem is that Keylight (or some part of the process) is noticeably amplifying the image noise! The gray areas after keying are just dancing pixel nightmares. I can't explain this. My mattes are perfectly opaque in foreground elements, and I'm applying no compression to the renders. It appears in RAM previews as well. Any ideas?
Doug Spice is offline   Reply With Quote
Old November 26th, 2006, 12:14 PM   #2
Major Player
Join Date: Jul 2003
Location: Oklahoma
Posts: 424
use primatte, i pulled much better keys from an hvx200 with it

Riley Harmon is offline   Reply With Quote
Old November 26th, 2006, 06:04 PM   #3
Major Player
Join Date: Feb 2004
Location: Philadelphia, PA, USA
Posts: 548
Yes, garbage mattes (via procedural keys or manual roto) are critical.

Also, you can use keylight to simply derive the matte, then apply the result as a mask to ensure that you bypass any color processing on the clip itself.
Nick Jushchyshyn Matchmoving, Compositing, TD
Nick Jushchyshyn is offline   Reply With Quote
Old June 2nd, 2008, 03:31 PM   #4
Great DV dot com
Join Date: Sep 2003
Location: Lewisville, NC
Posts: 78
It's not so much the HVX footage. Keylight defaults to using the Softlight method for Screen Matte/Replace Method, and that's where the noise in dark areas comes from. I've had this happen with F900 footage, shows up on dark fabric and in shadows.

Reset this to Hard Light or Source and see if the noise goes away!
John Jackman
John Jackman is offline   Reply With Quote
Old June 3rd, 2008, 09:28 AM   #5
Regular Crew
Join Date: Dec 2005
Location: Chicago, IL
Posts: 140
Ditto on the hard/soft light suggestion.

Also, the try changing the color-replacement color. It defaults to gray, I think: change that to a closer match to the new backgound color that you're comping over.

If nothing else works, switch to the "intermediate" View setting instead of "final result." That shuts off Keylight's color correction, and you then can use the basic spill supressor or other trick of your choice.

Also, if you've never seen this:
Andrew J Morin is offline   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

Omega Broadcast
(512) 251-7778
Austin, TX

(973) 335-4460
Mountain Lakes, NJ

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

(800) 238-8480
Glendale, 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 > Cross-Platform Post Production Solutions > Digital Compositing and Effects

Thread Tools Search this Thread
Search this Thread:

Advanced Search



All times are GMT -6. The time now is 04:52 AM.

DV Info Net -- Real Names, Real People, Real Info!
1998-2015 The Digital Video Information Network