Return-Path: Received: from mail-qa0-f48.google.com ([209.85.216.48] verified) by media-motion.tv (CommuniGate Pro SMTP 4.2.10) with ESMTP-TLS id 4890804 for AE-List@media-motion.tv; Sun, 04 Nov 2012 23:29:01 +0100 Received: by mail-qa0-f48.google.com with SMTP id c11so1660644qad.7 for ; Sun, 04 Nov 2012 14:31:58 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:x-gm-message-state; bh=K/PwvfRi4PIWC0zRDBm2699sXwmO82pwHs4G82AzYVo=; b=eeUvzmczWU2Bdp9oSf1pi1IGTYki95WmyfR6G+cJcTcck7F3AgVioTBGx/2cGL/Cfq oR1jhcOFr8TK8irCe0Mc4NOEhv4LbuJ5m49yMFZLhc6S48MznAYZS7v8aeTZ3OStuFQG uHDO1cSbUkZqwhzb1K7hErPu1ujcO4MHK6C74/kGC20kvpPcWJ7wlR9V4dVFH6tpT/ZE NmqCS8OBFqsjK0FMZQYhA8nYfD2RLt0mpVkbhM8+5KEmUr7q0dmrfu0dSOX2Lt5zYK0t tfgpDeb55bAgzPtPxg6ROWL3jowKbAzovCKpHyzC75DGpdJZv03XyG/axuWxGnAbnAE6 EVxg== MIME-Version: 1.0 Received: by 10.229.69.28 with SMTP id x28mr2918225qci.151.1352068318647; Sun, 04 Nov 2012 14:31:58 -0800 (PST) Received: by 10.49.128.65 with HTTP; Sun, 4 Nov 2012 14:31:58 -0800 (PST) In-Reply-To: References: Date: Sun, 4 Nov 2012 16:31:58 -0600 Message-ID: Subject: Re: [AE] pulling a better difference matte? From: Brian Higgins To: After Effects Mail List Content-Type: multipart/alternative; boundary=0021cc0226c6d8553d04cdb2ef7f X-Gm-Message-State: ALoCoQknA2BSulKiDCV0tWWmBTpSNfsgte6yM2VrQB292KAfK5xwNnE5v0flBthcIwWioUpJ6ugf --0021cc0226c6d8553d04cdb2ef7f Content-Type: text/plain; charset=ISO-8859-1 Difference mattes have gotten more useful with the advent of high-quality digital cameras, but still rarely work. It's easy for your brain to say "look, the actor is in one plate but not the other," but the computer can't tell what's an object and is only looking at differences in color. If your actor's skin tone is similar to the shelves behind him, you're hosed. I would look into the roto brush like Jack said, and maybe give the Furnace tools from the Foundry if you have access to Nuke. If not, I'd bite the bullet and start rotoing. If your actors are *really* flailing around, hand-painting the mattes may be quicker than yanking splines around. $.02, Brian On Sun, Nov 4, 2012 at 4:19 PM, Teddy Gage wrote: > Hello, I'm working on an indie film and they have presented me with > some "interesting technical challenges," to put it diplomatically. The > current shot I'm working on is two actors getting riddled with bullets, > with no practical effects or greenscreen. I am adding blood, bullet holes, > dust, smoke and glass. they are flailing about like rag dolls then go down. > It lasts about five seconds. There are rows of shelves behind them with > glass bottles that stay intact throughout the shot. In a separate shot, the > director then pulled the bottles off the shelves using strings, and the two > shots need to be composited together. If only the actors had been shot on > greenscreen, this would be easy. But there are enough changes between shots > that a difference key only gets me about 50% of the way there. However this > ancient effect is not 32-bit, has awful controls, and it's almost > impossible to get a clean difference matte; half the background is pulled > into the effect and I cannot cleanly separate the actors. > > Of course, I could roto actors out of the scene, then lay them on top of > the glasses breaking, but I'd like to avoid this. Are there any tools that > are better for pulling out a motion matte from a static background other > than difference matte? Or is there another way to do this I'm not thinking > of? > > The approach I currently have going is to pull a difference key of the > bottles flying off the shelves from the static shot, then to roto the > actors' arms etc. in just the regions where they intersect with the > bottles. This way it appears the bottles are being shot up behind the > actors, as they should be. This at least saves me from having to do a full > roto of each actor against the background. Would love to hear any other > suggestions, thanks > TG > > -- > Animator & Editor > www.teddygage.com > Brooklyn > > -- *brian higgins | creative director Sol Design 312.706.5500 higgins@soldesignfx.com soldesignfx.com * --0021cc0226c6d8553d04cdb2ef7f Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Difference mattes have gotten more useful with the advent of high-quality d= igital cameras, but still rarely work. =A0It's easy for your brain to s= ay "look, the actor is in one plate but not the other," but the c= omputer can't tell what's an object and is only looking at differen= ces in color. =A0If your actor's skin tone is similar to the shelves be= hind him, you're hosed. =A0I would look into the roto brush like Jack s= aid, and maybe give the =A0Furnace tools from the Foundry if you have acces= s to Nuke. If not, I'd bite the bullet and start rotoing. =A0If your ac= tors are *really* flailing around, hand-painting the mattes may be quicker = than yanking splines around.

$.02,
Brian

On Sun, Nov 4,= 2012 at 4:19 PM, Teddy Gage <teddygage@gmail.com> wrote:<= br>
=A0=A0=A0=A0 Hello, I'm working on an indie film and they have presente= d me with some "interesting technical challenges," to put it dipl= omatically. The current shot I'm working on is two actors getting riddl= ed with bullets, with no practical effects or greenscreen. I am adding bloo= d, bullet holes, dust, smoke and glass. they are flailing about like rag do= lls then go down. It lasts about five seconds. There are rows of shelves be= hind them with glass bottles that stay intact throughout the shot. In a sep= arate shot, the director then pulled the bottles off the shelves using stri= ngs, and the two shots need to be composited together. If only the actors h= ad been shot on greenscreen, this would be easy. But there are enough chang= es between shots that a difference key only gets me about 50% of the way th= ere. However this ancient effect is not 32-bit, has awful controls, and it&= #39;s almost impossible to get a clean difference matte; half the backgroun= d is pulled into the effect and I cannot cleanly separate the actors.

Of course, I could roto actors out of the scene, then lay them on top o= f the glasses breaking, but I'd like to avoid this. Are there any tools= that are better for pulling out a motion matte from a static background ot= her than difference matte? Or is there another way to do this I'm not t= hinking of?

The approach I currently have going is to pull a difference key of the = bottles flying off the shelves from the static shot, then to roto the actor= s' arms etc. in just the regions where they intersect with the bottles.= This way it appears the bottles are being shot up behind the actors, as th= ey should be. This at least saves me from having to do a full roto of each = actor against the background. Would love to hear any other suggestions, tha= nks
TG

--
Animator & Editor
ww= w.teddygage.com
Brooklyn




--
brian higgins | creative director
Sol =A0Design
312.706.5500
higgins@soldesignfx.com
soldesignfx.com



--0021cc0226c6d8553d04cdb2ef7f--