Green Screen red dots at DVinfo.net

Go Back   DV Info Net > Special Interest Areas > Techniques for Independent Production

Techniques for Independent Production
The challenges of creating Digital Cinema and other narrative forms.


Reply
 
Thread Tools Search this Thread
Old March 6th, 2005, 09:15 PM   #1
New Boot
 
Join Date: Feb 2005
Location: Tigard, Oregon
Posts: 6
Green Screen red dots

Can someone explain to me what those little red dots mean on the green or blue screen? I am assuming they are reference points for tracking but I just can't seem to comprehend how it all works together.

Thanks a million

Bev Standish
Wolfsong Studios
__________________
Bev Standish
Wolfsong Studios
Bev Standish is offline   Reply With Quote
Old March 7th, 2005, 04:19 AM   #2
RED Code Chef
 
Join Date: Oct 2001
Location: Holland
Posts: 12,514
They are indeed for tracking, sometimes with a different color
(like white) as well. Mainly to see how camera moves where done
and allow to track those shots for compositing reasons.

What else do you want to know?
__________________

Rob Lohman, visuar@iname.com
DV Info Wrangler & RED Code Chef

Join the DV Challenge | Lady X

Search DVinfo.net for quick answers | Buy from the best: DVinfo.net sponsors
Rob Lohman is offline   Reply With Quote
Old March 10th, 2005, 04:34 PM   #3
New Boot
 
Join Date: Feb 2005
Location: Tigard, Oregon
Posts: 6
Red Dots

Thanks so much for replying to my post. I am trying to visualize how these reference dots work. My question is, what is the workflow? I have a CG background and am wanting to composite live actors against a green screen. So I understand I key out the green out but leave the red dots? What do I do with the dots?

Thanks again

Bev
__________________
Bev Standish
Wolfsong Studios
Bev Standish is offline   Reply With Quote
Old March 10th, 2005, 05:30 PM   #4
Inner Circle
 
Join Date: Sep 2002
Location: San Mateo, CA
Posts: 3,840
The reference dots are for camera tracking movement. In other words, they allow you to follow the camera movement, without any depth of field reference that you normally get through visual references.

The actors are standing in a green room. The camera pushes in, booms up and swings left. Hard to know what's happening to the background images... when there's nothing but green background.

This information is then compared with the matte background, so that the camera movement of the background matches the camera movement of the foreground. (Such 'camera movement' might actually be a simulated cg background of course)

Follow?
Richard Alvarez is offline   Reply With Quote
Old April 2nd, 2005, 11:16 PM   #5
Regular Crew
 
Join Date: Feb 2004
Location: Austin, TX
Posts: 182
Right - to just say the same thing another way:

1) Shoot the greenscreen with the tracking dots.
2) Import this into your CG application, (play it as a background, keying out the green) and then put fixed objects in the CG scene at the same location as the tracking dots.
3) Now move your CG camera such that your synthetic (CG) tracking dots 'move' the same way as the tracking dots in the original footage.

This means you have matched a CG camera move to the move the real camera did.

This will allow your synthetic background to match up with the real camera move on the live action.
__________________
http://www.aqua-web.com
Jonathon Wilson 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 > Special Interest Areas > Techniques for Independent Production

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



Google
 

All times are GMT -6. The time now is 08:06 AM.


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