Camera+depth of field

[Dan Ebberts]

You could use something like this (not tested, so there might be typos):

strtFocusChg = 4; // start at 4 seconds
focusChgDur = 2; // focus change duration
d1 = length (thisComp.layer(“Layer 1”).transform.position, transform.position);
d2 = length (thisComp.layer(“Layer 2”).transform.position, transform.position);
ease(time,strtFocusChg, strtFocusChg + focusChgDur, d1,d2)

Dan

[Paolomart]

Thanks Dan.
I’ll try as soon as I can.

Paolo

[Darby Edelen]

I just did something like this. In my case I only had 2 layers I was changing focus between so I created a Null (“Focus Control”) with 2 layer control effects applied and 1 slider control applied (it’s important that they be created in that order for this expression). The goal was to focus on the first layer control layer when the slider was at 0 and the second when the slider was at 1. Here’s the code I applied to the focus property:


m = 300; //minimum focus distance
a = thisComp.layer("Focus Control").effect(3)("Slider"); //The slider that determines which layer is in focus

l1 = thisComp.layer("Focus Control").effect(1)("Layer"); //The first layer to focus on
l2 = thisComp.layer("Focus Control").effect(2)("Layer"); //The second layer to focus on

c = toWorld([0,0,0]); //The camera's position
p1 = l1.toWorld(l1.anchorPoint); //The first layer's position
p2 = l2.toWorld(l2.anchorPoint); //The second layer's position
p = linear(a, 0, 1, p1, p2); //When the slider on the Focus Control layer is at 0 or below use the first layer's position, when it is at 1 or above use the second layer's position

v1 = p - c; //The v1 vector is the vector between the layer's position and the camera's position
v2 = toWorldVec([0,0,1]); //The v2 vector is a vector pointing down the camera's z axis
v = dot(v1, v2); //Project the v1 vector onto the v2 vector (thanks Dan!)
Math.max(m, v); //Return the larger of either 'm' or 'v'


Since the camera began far behind the layers to focus on, in my case, I needed a minimum value for the focus. So I created the ‘m’ value to contain a minimum value, you could put a value that works better for you in there.

Darby Edelen
Designer
Left Coast Digital
Santa Cruz, CA

[Paolomart]

This is pretty nice.
I wonder if could be applied to 3 or more layers like to have a handheld camera effects.

Paolo