Animating Z-Depth

[Jock]

I'm currently learning After Effects and its raising a few issues in both that and in Max.

 

One thing i want to do is animate the zdepth but i want to do it in post so i have control over it and can easily get rid if i choose to.

 

Now i know i can render a zdepth pass but from what i can see it cant be animated, so for example if i keep the camera in one position but first i want it to focus on a close object, then i want it to focus on the rest of the room. I can only seem to set up the settings and they are what they, they wont say animate, letting the figures rise/fall over time. But i'd need this to then take it into AE and applay it as a mask wouldnt i?

 

So basically i can get it to work for a still but not for an animation.

 

Thanks

[notamondayfan]

I presume you are wanting to animate the depth of field in AE? You shouldnt need to animate the Zdepth pass its self, as all this contains is the distance data, instead you should be animating your effect in AE. Are you using any plugins for AE? I can recomend the Frichluft lens effects plugin, it works brilliantly for DOF.

 

Dean

[Jock]

Yeah your right, i want to do the pass so i can animate the depth in AE.

 

When you say you shouldnt need to animate the zdepth itself, i thought i'd need to because my render would be set so for example some close stuff is in focus, and the background stuff isnt, but then wouldnt i need a different setting to be able to say inverse that, so the background is in focus, because the data in the zdepth is fixed, meaning whats in focus is always in focus.

 

I'm not using any plugins at the moment as i've still to get round to putting my thoughts into action but hope to do so soon. I'll give that plugin a look when i do.

 

Cheers for the help!

[Stephen Thomas]

Dean's right, the Z depth doesn't determine your point of focus, it just gives you the range. Add a Lens blur effect to your RGB layer, then select your Z Depth layer as your 'Depth map layer' and leave 'Depth map channel' set to luminance. Now you can adjust/animate the 'Blur focal distance' to change point of focus and 'Iris radius' to change how shallow your depth of field is.

 

It goes without saying that you don't want to be applying any DOF effects in 3ds max to your render, I hope.

[notamondayfan]

DOF using zdepth works by picking a colour value (grey scale) that you want to be in focus, then everything else is out of focus. You can select white, black, or grey values to be in focus, then the rest will be blured. You then animate the colour value of what you want to be in focus.

Sorry for the crap explanation, it's one of those things I could show you in 1 min, but take days explaining it!!

 

Dean

[Jock]

Excellent, just tried it and it worked a treat.

 

I didnt think it would that easy, i figured you'd have to animate the pass itself.

 

Thanks for the help guys.