Thanks.  I was able to workaround it, but I thought I would relay this for RL.

Are you able to re-create this blackout situation in in a new scene? I can't get it to do that. Maybe just toss that camera and put in a new one? You are correct that the DOF plain is always perpendicular to the lens. If you set it really narrow, you can see the results in your scene.

I know that DOF does not track your object, it has to be keyed. Try putting a new depth key (pick an object) in the problem area of the timeline.

I don't have any good ideas yet. ;)

Experiment test:
You might try not picking a target, but rather just use numbers to determine the focus distance and focus range. Then animate those numbers to keep your target in focus as the camera moves around it.

I'm working on a new scene - this is the first time I've actually done a complete scene with iClone 6 - and I ran into a very strange issue with Depth of Field:



This diagram shows how my scene is setup.  There's a camera attached to a path.  It moves clockwise to the end of the path, over about 1,000 frames.  It's targeted at a cube I'm using for Pan/Tilt. And DOF is ACTIVATED.  The SUBJECT is the DOF TARGET.  

In my render, I'm making heavy use of HDR, and Supersampling.  The subject is speaking, so there's audio as well.

As the camera moves along the path, it hits the BLACKOUT, after which every frame is rendered black.    At first I thought this was a computer issue, or a GPU issue.  I had an issue, earlier this year, with smoothing that was GPU related, and a driver update cured it.  But this scene - whether rendered in UHD or HD - is not maxing out my system.  

I noticed when I scrubbed the timeline, I hit a black frame at the BLACKOUT.  As I moved the playhead forward, everything resumed normally after this frame.  So obviously I looked for objects which might be causing an obstruction.  I turned every object in the scene off, but I was still getting this BLACKOUT.  

So I started looking at the camera settings, and found that if I TURNED DOF OFF - the BLACKOUT WENT AWAY.  I was able to REACTIVATE DOF, after the place in the timeline where the BLACKOUT occurred. 

Notice that the DOF PLANE, at the start of the shot, runs perpendicular to the angle of the camera - roughly inline with where the BLACKOUT occurs.  Now I assume that the DOF PLANE DOES NOT REMAIN STATIONARY, and moves with the camera.  Am I right about this?  Otherwise, perhaps the camera "blacks out" when it crosses the DOF PLANE?

Anybody?  Thanks ;)