From: "=?utf-8?Q?Mathias_M=C3=B6hl?=" Received: from mo4-p00-ob.smtp.rzone.de ([85.215.255.20] verified) by media-motion.tv (CommuniGate Pro SMTP 6.1.0) with ESMTPS id 6437670 for AE-List@media-motion.tv; Wed, 18 Apr 2018 08:42:23 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; t=1524034078; s=strato-dkim-0002; d=mamoworld.com; h=In-Reply-To:To:References:Date:Subject:Message-Id:Content-Type:From: X-RZG-CLASS-ID:X-RZG-AUTH:From:Subject:Sender; bh=AVft28T9odX27aycKpdpFLhMalYWmB1ohmvutGHTh3M=; b=FsgtFadJl+0ED1qoz3+OqRoBYxPjM1Om63FJDyVNPodWMwn8LjL6n9S0fNKhz6P/tR gdnoib43vxUEHRpdpktId+iXJuyYXU1Mci0xzbhYzWGbfngRCLfyFXLd54t4zeF+mnSU M4MZwh1M4hPxj7f20dywK3kmqxvUUNc2yug9ZsXHyiibtfubhLa9yhniDcEIpx7Ki5ih L0BJ+Q7QaSyu0cai5cXLK90XBC9WjNYu1KpriDCg3tPCQJZK4X2A657Zpj9mYhdGs1A3 55qg3d/Z/J0XFQvJt/Fxz1nrKA2fy5bDuGS1lLLP6cHspxotO5yUEF+Ct3jo6aS0PYc7 rh8g== X-RZG-AUTH: :JWICemClevKDgu8HjcNJMjRl593UXKPCWwh3HJPaR2BqiNKNpdy/gK8tufbZZZLzvOPcys8J X-RZG-CLASS-ID: mo00 Received: from mathiasmac-3.fritz.box by smtp.strato.de (RZmta 43.2 DYNA|AUTH) with ESMTPSA id f064a4u3I6lvgY2 (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (curve secp521r1 with 521 ECDH bits, eq. 15360 bits RSA)) (Client did not present a certificate) for ; Wed, 18 Apr 2018 08:47:57 +0200 (CEST) Content-Type: multipart/alternative; boundary="Apple-Mail=_01385603-EF71-452E-98CD-581F3F3849A2" Message-Id: Mime-Version: 1.0 (Mac OS X Mail 9.3 \(3124\)) Subject: Re: [AE] Inverse Square Law for glows Date: Wed, 18 Apr 2018 08:47:56 +0200 References: To: After Effects Mail List In-Reply-To: X-Mailer: Apple Mail (2.3124) --Apple-Mail=_01385603-EF71-452E-98CD-581F3F3849A2 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Here is a great Ae tutorial about building your own glow preset based on = inverse square law: https://www.youtube.com/watch?v=3D--LsJ0DErgM = Cheers, Mathias mamoworld.com simplify your cgi Dr. Mathias M=C3=B6hl Marlow 52 , 18551 Sagard, Germany Phone +49 (0)38302 - 88 75 61 info@mamoworld.com > On 18 Apr 2018, at 01:37, Chris Zwar wrote: >=20 > If you want to do it mathematically then it=E2=80=99s more complex = than you think, as you need to consider the gamma of the workspace = you=E2=80=99re using. >=20 > Making something glow by stacking up multiple layers with different = blurs is faking it, but probably the best way to do it in 8 or 16 bit = modes. It=E2=80=99s the way i do it too, although I use the screen mode = (not add), and I usually have a desaturated layer near the top set to = classic colour dodge to adjust the =E2=80=9Chotness=E2=80=9D. =46rom a = mathematical perspective, you=E2=80=99re not just looking at the blur = profile but also the gamma of the workspace so this multiple layer = approach is going to be difficult to calculate. >=20 > The alternative approach is to comp in 32 bit linear mode, where you = don=E2=80=99t need to stack up multiple layers. You just have your = source layer and make the colour super hot. Then you blur it and the = blur naturally spreads out the light. The falloff will depend on the = type of blur you use. I did ask a while ago (for exactly the same = reason as you) if there=E2=80=99s a blur with an adjustable profile = including inverse square, which would be very useful for comping glows = in 32 bit float mode. I can=E2=80=99t remember the answer, but = there=E2=80=99s something for you to look at. >=20 > So basically - multiple layers using add/screen and blur is an 8/16 = bit fudge for a gamma working space like sRGB/HDR. A single, super hot = layer with a single blur in 32 bit linear float is the more natural = approach. >=20 > Or you can just use a plugin that does it, as lloyd suggests :-) >=20 >=20 > -Chris >> On 18 Apr 2018, at 4:28 am, Byron Nash > wrote: >>=20 >> So, if I were applying that to say, the blur of a layer, what would = be the "distance" variable? I'm stacking several layers with Add = transfer modes and variable amounts of blur. >>=20 >> On Tue, Apr 17, 2018 at 2:17 PM Walter Soyka > wrote: >> The inverse square law states that intensity is inversely = proportional to the square of the distance from the source. = Symbolically: >> intensity =3D 1 / (distance^2) >>=20 >> Doing a little math, when the distance is 1, the intensity is 1. When = the distance is 2, the intensity is 0.25. When the distance is 3, the = intensity is 0.111. When the distance is 4, the intensity is 0.0625. >>=20 >> walter soyka =E2=96=BC keen live=20 >> walter@keenlive.com >>=20 >> On Tue, Apr 17, 2018 at 1:46 PM, Byron Nash > wrote: >> Always the consummate salesman Lloyd! ;-)=20 >>=20 >> I think this was more of an experiment to see if I could do it myself = and understand the math a bit better.=20 >>=20 >> On Tue, Apr 17, 2018 at 1:05 PM Lloyd Alvarez = > wrote: >> Oooooorrrr you could just use Real Glow = ! ;-) >>=20 >> Cheers, >> Lloyd >>=20 >> On Tue, Apr 17, 2018 at 12:16 PM, Byron Nash > wrote: >> I'm trying to roll my own setup for a better glow. If I'm trying to = follow the inverse square law to do the math, would I half/double the = amounts at each iteration? Or square root? >>=20 >>=20 >=20 --Apple-Mail=_01385603-EF71-452E-98CD-581F3F3849A2 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8 Here is a great Ae tutorial about building your own glow = preset based on inverse square law:
https://www.youtube.com/watch?v=3D--LsJ0DErgM

Cheers,
Mathias



mamoworld.com
simplify your cgi

Dr. Mathias M=C3=B6hl
Marlow 52 , 18551 Sagard, Germany
Phone +49 = (0)38302 - 88 75 61
info@mamoworld.com


<= /div>

On 18 Apr 2018, at 01:37, Chris Zwar <AE-List@media-motion.tv> wrote:

If you want to do it = mathematically then it=E2=80=99s more complex than you think, as you = need to consider the gamma of the workspace you=E2=80=99re using.

Making something glow by = stacking up multiple layers with different blurs is faking it, but = probably the best way to do it in 8 or 16 bit modes.  It=E2=80=99s = the way i do it too, although I use the screen mode (not add), and I = usually have a desaturated layer near the top set to classic colour = dodge to adjust the =E2=80=9Chotness=E2=80=9D.  =46rom a = mathematical perspective, you=E2=80=99re not just looking at the blur = profile but also the gamma of the workspace so this multiple layer = approach is going to be difficult to calculate.

The alternative approach is to comp in = 32 bit linear mode, where you don=E2=80=99t need to stack up multiple = layers.  You just have your source layer and make the colour super = hot.  Then you blur it and the blur naturally spreads out the = light.  The falloff will depend on the type of blur you use. =  I did ask a while ago (for exactly the same reason as you) if = there=E2=80=99s a blur with an adjustable profile including inverse = square, which would be very useful for comping glows in 32 bit float = mode.  I can=E2=80=99t remember the answer, but there=E2=80=99s = something for you to look at.

So basically - multiple layers using = add/screen and blur is an 8/16 bit fudge for a gamma working space like = sRGB/HDR.  A single, super hot layer with a single blur in 32 bit = linear float is the more natural approach.

Or you can just use a plugin that does = it, as lloyd suggests :-)


-Chris
On 18 Apr 2018, at 4:28 am, Byron Nash <AE-List@media-motion.tv> wrote:

So, if I were applying that to say, the blur of a layer, what = would be the "distance" variable? I'm stacking several layers with Add = transfer modes and variable amounts of blur.

On Tue, Apr 17, 2018 = at 2:17 PM Walter Soyka <AE-List@media-motion.tv> wrote:
The inverse square law states = that intensity is inversely proportional to the square of the distance = from the source. Symbolically:
intensity =3D 1 / = (distance^2)

Doing a = little math, when the distance is 1, the intensity is 1. When the = distance is 2, the intensity is 0.25. When the distance is 3, the = intensity is 0.111. When the distance is 4, the intensity is = 0.0625.

walter soyka =E2=96=BC keen live 
walter@keenlive.com

On Tue, Apr 17, 2018 at 1:46 = PM, Byron Nash <AE-List@media-motion.tv> wrote:
Always the consummate salesman Lloyd! ;-) 

I think this was more of = an experiment to see if I could do it myself and understand the math a = bit better. 

On Tue, Apr 17, 2018 = at 1:05 PM Lloyd Alvarez <AE-List@media-motion.tv> wrote:
Oooooorrrr you could just use Real Glow! ;-)

Cheers,
Lloyd

On Tue, Apr 17, 2018 at 12:16 = PM, Byron Nash <AE-List@media-motion.tv> wrote:
I'm trying to roll my own setup for a better glow. If I'm = trying to follow the inverse square law to do the math, would I = half/double the amounts at each iteration? Or square root?





= --Apple-Mail=_01385603-EF71-452E-98CD-581F3F3849A2--