Depth of Field Blur

[Adolfo Rozenfeld]

One thing that could make things a bit more realistic is lowering the Blur amount in Camera Settings. While the Aperture/F-stop parameter controls the size of the DOF area, Blur controls how blurred the items out of the DOF area actually are (ie, shameless cheating!)

One trick that could work if you’re not doing per-character text animation but animating whole layers is bypassing camera DOF simulation completely and apply the Lens Blur effect (which has advanced Bokeh controls, like number/shape of the iris blades) to each layer and write an expression that links blur intensity to distance from camera, using length() to figure this distance.
The rendering times could be frightening, though.

Adolfo Rozenfeld · Adobe

[Frank Muldoon]

I guess the blur is really a fake not optical. 8,16 or 32 bit doesn’t really help either. The expression solution is a bit more than I want to get into.
On a slightly different point, what is the best way to get focal distance to follow point of interest. It seems very difficult to lock the focus on an object while the camera is moving.

Frank

[Adolfo Rozenfeld]

Frank: Lens Blur is an amazing imitation of the optical qualities of an out of focus lens, including the blown-out highlights, the shape of the iris blades, etc. Unfortunately, it’s a 2D effect (and AE doesn’t offer a way to extract a grayscale depth map from a 3D scene, which is something Lens Blur could use to simulate DOF). That’s why I suggested the “Lens Blur driven with expressions” solution. But I understand that can be scary (and very render intensive).

That said, there is very high end work out there which makes use of the built-in DOF in AE cameras. I guess it’s more or less realistic depending on context. In many cases, lowering the blur threshold worked for me. Especially when the DOF is really shallow.

How to link focus distance to Point of Interest… Enable the expression field for the Focus Distance property (Alt click the stopwatch) and then point with the pick-whip to the POI property to connect it. From that point on, it will be linked to POI as you adjust it.

Adolfo Rozenfeld · Adobe

[Frank Muldoon]

That doesn’t really work since POI is a XYZ coordinate in space and Focus Distance is a distance from the camera independent of spacial coordinates. The correct expression would have to be the distance between camera and POI. What would that formula be?

Frank

[Adolfo Rozenfeld]

Oh, of course.
I was so concentrated trying to explain how to use the pick whip 🙂
Add this expression to Focus Distance:
length(position, pointOfInterest)

Adolfo Rozenfeld · Adobe

[Frank Muldoon]

That is perfect. Thank you so much!

Frank

[Jeremy Allen]

It’s also useful to create a 3d null and use that for your point of interest. You could still use the same expression: Link the focal length to the point of interest, which is linked to the position of the null object. That way you can freely move the null around when you need to change the POI. Works like a charm, and easier to move around than the camera’s built-in POI handle.

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8core MacPro, 3.0 GHZ, 10GB RAM, OSX 10.5.2

AE CS3

[Frank Muldoon]

Very clever. I like this idea.
Is there any way to disable the POI? In many situations it is a pain to have to deal with. Some times I would like to just use camera rotation to set the shot. When I use the “C” camera controls it adds all these POI keyframes that make the motion jerky.

Frank

[Andy George]

If you right click on the camera you can select Transform>auto-orient to disable the point of
interest. You can also quickwhip the POI position to your camera’s position, locking them together.

[Adolfo Rozenfeld]

Select the Camera and go to Layer > Transform > Auto-Orient and turn it off.

Adolfo Rozenfeld · Adobe