layer transparency distance from camera

[Franky Torres]

currently I believe their opacity is determained by distance from camera in z space

[Dan Ebberts]

Well, I’m lost. What I’m picturing doesn’t make any sense. Maybe somebody else (with more imagination) can jump in and help out.

Dan

[Sam Moulton]

From what I understand you want to pull back through a tunnel of images and as they get a certain distance from the camera you want them to fade out.

The part I don’t understand is why visibility matters if the layers are behind the camera, because you can’t see them when they are behind the camera. Dan’s expression should work just fine if you establish the proper distances for the images to start and end their fade out.

[Chad Smith]

Would a similar setup work for applying a Fast Blur to a layer based on distance(fake DOF) and if so what would that expression look like? Thanks in advance for any help you can offer.

[Jim Darski]

Thanks so much. This works very well.
My question is: is there a way to adjust this expression to fade in when close to the camera in addition to fading out when away from the camera? For example: the object is transparent when closer than 50 from camera. From 100 to 200 its transparency goes from 0 to 100. And then 500 to 1500 it fades out as you have it now.
I was trying to put additional startFade and endFade commands, but it didn’t work.

jim

[Dan Ebberts]

I don’t understand the closer than 50 part (it seems like that’s covered by the 100 to 200 range) but here’s one way to do two ranges:

C = thisComp.activeCamera;
startFade1 = 100;
endFade1 = 200;
startFade2 = 500;
endFade2 = 1500;
d = length(toWorld(anchorPoint),C.toWorld([0,0,0]));
if (d < (endFade1+startFade2)/2)
linear(d,startFade1,endFade1,0,100)
else
linear(d,startFade2,endFade2,100,0)

[Jim Darski]

This is exactly what I need! I made a mistake and should have said closer than 100… But you got it. Basically I tried to say that I need to set up 2 ranges.
Thanks so much!
j.

[Nelson Rayner]

Hey Everyone!

I have several layers (in the Z axis) of pre-composed image grids (with some images missing), that a camera is moving through and around.

What I’m trying to do is move around and focus on some of these images whilst the layers in the background are more transparent as to make the composition less busy and to focus on the images in the foreground. Also, as the camera moves through the images, the grids become transparent just before they hit the camera.

I’m having trouble with Dan’s script as when the camera is moving through and around the grids, obviously the anchor point of each becomes further away from the camera and the grids become less opaque.

What I’m wondering is….if there a way to let the script reference the z position of the layer rather than the anchor point position so as to negate this issue?

Thanks in advance for helping!

[Adam Nelson]

Awesome expression, Dan! This really got me out of a jam today on a quick turnaround and it makes me want to learn a lot more about the toWorld command.

Thanks!

[Stuart Simpson]

Hi all,

If I’m reading this correctly I have the same issue. I’ve been using this Dan’s expression (below) for the opacity of a series of layers. With the camera in a master comp and the 3D layers in a pre-comp within the Master comp (the pre-comp is a 3D layer in the master comp with transformations collapsed).

The problem is the x-position seems to be affecting the opacity and I need just the z position. Any ideas greatly appreciated! 🙂

startFade = thisComp.layer("opacity controller").effect("start")("Slider");
endFade = thisComp.layer("opacity controller").effect("end")("Slider");
C = comp("MASTER").activeCamera;
CL = comp("MASTER").layer(thisComp.name);
CL.toWorld(toWorld(anchorPoint));
d = length(CL.toWorld(toWorld(anchorPoint)),C.toWorld([0,0,0]));
linear(d,startFade,endFade,100,0)