Return-Path: Received: from mail-wg0-f53.google.com ([74.125.82.53] verified) by media-motion.tv (CommuniGate Pro SMTP 4.2.10) with ESMTP-TLS id 4781028 for AE-List@media-motion.tv; Fri, 20 Jul 2012 18:39:07 +0200 Received: by wgbfm10 with SMTP id fm10so3027354wgb.22 for ; Fri, 20 Jul 2012 09:42:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=hWmfvSH03sC9+5q7YVA1/mP1x6SKjjax4lOWS2cwBkA=; b=BjRq0Ktg34eCD0D7qDXFGJMIER8siKtTJ6peW+IE4xaLcuRZLIF+PkiMV8mUUQboRg E1YfBtywaWWZIscetSnQdrqv+dGqnrGmGLim91UEoWRngb4BzDTLx+qJ0eroyOaU61IA Y8sAfKgqEQjUEF8vgBU7DaYYug8Q6ovimJGovVx7zYI0szbQwyKnLJDvbVcT97rIL/gO ezS/FqtAV+UiCl1EMK1+VLgJ/SC32Qggcfw9tEITKCGMTVaS7H6+iheDwu5OsyBOhdRI XKkKb5yPKjLKJ+6rREymdlDQa+xYKQvrWesoRaKS2Rs38KLkFOZEurYIeIIIXX8Qesww G9lA== MIME-Version: 1.0 Received: by 10.216.139.17 with SMTP id b17mr4367710wej.8.1342802579478; Fri, 20 Jul 2012 09:42:59 -0700 (PDT) Received: by 10.216.245.69 with HTTP; Fri, 20 Jul 2012 09:42:59 -0700 (PDT) In-Reply-To: References: Date: Fri, 20 Jul 2012 18:42:59 +0200 Message-ID: Subject: Re: [AE] Issue with Transparency in CS6 Raytracing From: =?ISO-8859-1?Q?S=E9bastien?= To: After Effects Mail List Content-Type: multipart/alternative; boundary=0016e6d64830c0d9d004c545968e --0016e6d64830c0d9d004c545968e Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Thanks Mylenium, Chrsi & Todd, that's what i've done while sending this bottle in the AE sea. I just lowered the opacity to fake the transparency. But I'll use that black & white solution from now on to get a more good looking result. I'll be sure to add a feature request of course ! Cheers, Seb 2012/7/20 Todd Kopriva > Chris beat me to it, so I'll just chime in to say "yeah, what he said". > > > -----Original Message----- > > From: After Effects Mail List [mailto:AE-List@media-motion.tv] On > > Behalf Of Chris Meyer > > > > A subtle but important point in CS6 with ray tracing is to distinguish > > between Opacity and Transparency. > > > > Opacity alters the alpha channel for a layer; Transparency does not. If > > you create some extruded text in an otherwise blank comp, and either > > move the cursor across it while watching the RGBA values in the Info > > panel (or simply toggle on the Transparency Grid), you'll observe that > > a fully-transparent object with Opacity =3D 100% has an alpha value of > > 100% and does not pass the transparency grid through. > > > > Now, an admittedly confusing (but often desirable) quirk in CS6 is that > > if you place a 2D layer behind this transparent 3D layer _inside the > > same composition_, you can "look through" the transparent-but-opaque 3D > > layer and see the 2D layer. (It won't be refracted - only 3D layers get > > refracted by other 3D layers - but you'll see it.) > > > > So if you want to create a transparent object in AE, and render with an > > alpha that represents this "transparency", you'll need to fake it. What > > I used to do in dedicated 3D programs (which often have the same quirk) > > is render a second alpha-only pass and reduce the opacity of the semi- > > transparent objects just for that pass. You might get a better fake by > > placing a black solid behind, rendering the RGB, and converting that > > RGB pass into a grayscale alpha channel; this will show the effects of > > Transparency Rolloff. > > > > But I agree that it would be a nice feature request for AE to allow > > exporting of an alpha channel that matches what it does internally if > > there is a 2D layer behind in the same composition. In the meantime, > > think of it as being like exporting a layer with a blending mode: The > > blending mode only interacts with layers inside the same composition; > > not with layers composited outside the program. > > > > hope that helps - > > Chris > > > > > > > > > > On Jul 20, 2012, at 8:31 AM, mylenium@mylenium.de wrote: > > > > > > Either it's a design feature (set Alpha to opaque to avoid > > degenerate generate colors with premultiplied backgrounds) or a bug > > (premature termination of the ray evaluation). Whatever it is, probably > > nothing you can fix. > > > > > > > > Mylenium > > > > > > > > [Pour Myl=E8ne, ange sur terre] > > ----------------------------------------- > > www.mylenium.de > > > > > > > > > > > > > > "S=E9bastien" hat am 20. Juli 2012 um 14:46 > > geschrieben: > > > > > > > > Hi gang, > > > > I have to export the alpha channel of my comp, nothing > > really fancy at first, but then I noticed that my semi-transparent > > extruded shape objects are considered opaque. > > > > You can see here on my screenshot: > > https://www.dropbox.com/s/1f4u9v85d54sw7w/transparency.png The selected > > object is 45% opaque, and I should somehow see the checkboard through > > it, but no, the transparency is filled with some default black > > environment. > > > > > > At first I thought it was because my difraction was at 1.= 5 > > but no matter what value I change, it's always looking opaque when I > > put it against a transparent background (when I put an object behind it > > behaves correctly, it's only when the bg is transparent. > > > > Any idea how to circumvent this ? Is it intended behavior= ? > > (i'm quite new to Raytracing) > > > > Thanks ! > > > > Cheers, > > > > Seb > > > > -- > > S=E9bastien > > > > L'ebook que Nicolas ne trouve pas tr=E8s dr=F4le, mais qu= e tout > > le monde adore > > politikaillera.fr > > > > > > > > > > > +---End of message---+ > To unsubscribe send any message to > --=20 S=E9bastien L'ebook que Nicolas ne trouve pas tr=E8s dr=F4le, mais que tout le monde ad= ore *politikaillera.fr* --0016e6d64830c0d9d004c545968e Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Thanks Mylenium, Chrsi & Todd,

that's what i've done whi= le sending this bottle in the AE sea. I just lowered the opacity to fake th= e transparency. But I'll use that black & white solution from now o= n to get a more good looking result.

I'll be sure to add a feature request of course !

Cheers,
Seb

2012/7/20 Todd Kopriva <kopriva= @adobe.com>
Chris beat me to it, so I'll just chime = in to say "yeah, what he said".

> -----Original Message-----
> From: After Effects Mail List [mailto:AE-List@media-motion.tv] On
> Behalf Of Chris Meyer
>
> A subtle but important point in CS6 with ray tracing is to distinguish=
> between Opacity and Transparency.
>
> Opacity alters the alpha channel for a layer; Transparency does not. I= f
> you create some extruded text in an otherwise blank comp, and either > move the cursor across it while watching the RGBA values in the Info > panel (or simply toggle on the Transparency Grid), you'll observe = that
> a fully-transparent object with Opacity =3D 100% has an alpha value of=
> 100% and does not pass the transparency grid through.
>
> Now, an admittedly confusing (but often desirable) quirk in CS6 is tha= t
> if you place a 2D layer behind this transparent 3D layer _inside the > same composition_, you can "look through" the transparent-bu= t-opaque 3D
> layer and see the 2D layer. (It won't be refracted - only 3D layer= s get
> refracted by other 3D layers - but you'll see it.)
>
> So if you want to create a transparent object in AE, and render with a= n
> alpha that represents this "transparency", you'll need t= o fake it. What
> I used to do in dedicated 3D programs (which often have the same quirk= )
> is render a second alpha-only pass and reduce the opacity of the semi-=
> transparent objects just for that pass. You might get a better fake by=
> placing a black solid behind, rendering the RGB, and converting that > RGB pass into a grayscale alpha channel; this will show the effects of=
> Transparency Rolloff.
>
> But I agree that it would be a nice feature request for AE to allow > exporting of an alpha channel that matches what it does internally if<= br> > there is a 2D layer behind in the same composition. In the meantime, > think of it as being like exporting a layer with a blending mode: The<= br> > blending mode only interacts with layers inside the same composition;<= br> > not with layers composited outside the program.
>
> hope that helps -
> Chris
>
>
>
>
> On Jul 20, 2012, at 8:31 AM, m= ylenium@mylenium.de wrote:
>
>
> =A0 =A0 =A0 Either it's a design feature (set Alpha to opaque to a= void
> degenerate generate colors with premultiplied backgrounds) or a bug > (premature termination of the ray evaluation). Whatever it is, probabl= y
> nothing you can fix.
>
>
>
> =A0 =A0 =A0 Mylenium
>
>
>
> =A0 =A0 =A0 [Pour Myl=E8ne, ange sur terre]
> =A0 =A0 =A0 -----------------------------------------
> =A0 =A0 =A0 www.m= ylenium.de
>
>
>
>
>
>
> =A0 =A0 =A0 "S=E9bastien" <yenaphe@gmail.com> hat am 20. Juli 2012 um 14:46
> geschrieben:
>
>
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 Hi gang,
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 I have to export the alpha channel of my c= omp, nothing
> really fancy at first, but then I noticed that my semi-transparent
> extruded shape objects are considered opaque.
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 You can see here on my screenshot:
> https://www.dropbox.com/s/1f4u9v85d54sw7w/transparency.p= ng The selected
> object is 45% opaque, and I should somehow see the checkboard through<= br> > it, but no, the transparency is filled with some default black
> environment.
>
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 At first I thought it was because my difra= ction was at 1.5
> but no matter what value I change, it's always looking opaque when= I
> put it against a transparent background (when I put an object behind i= t
> behaves correctly, it's only when the bg is transparent.
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 Any idea how to circumvent this ? Is it in= tended behavior ?
> (i'm quite new to Raytracing)
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 Thanks !
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 Cheers,
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 Seb
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 --
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 S=E9bastien
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 L'ebook que Nicolas ne trouve pas tr= =E8s dr=F4le, mais que tout
> le monde adore
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 politikaillera.fr <http://politikaillera.fr/>
>
>
>
>


+---End of message---+
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--
S=E9bastien

L= 9;ebook que Nicolas ne trouve pas tr=E8s dr=F4le, mais que tout le monde ad= ore
politikail= lera.fr
--0016e6d64830c0d9d004c545968e--