About modifying keyframe properties
Each keyframe that is assembled into a track is a snapshot of the properties of the object or objects contained within the track at a certain time. At each keyframe, there is a value stored for the property of the object or objects contained within the track that can be altered to achieve a desired effect. Individual keyframe properties can be disabled to allow interactive control or to combine the effect of tracks in certain parts of the animation. Disabling keyframe properties is also useful to turn off the effect of individual keyframes without actually removing them from the track. When a keyframe property is disabled, a special string (—) will appear in the keyframes table (on the Keyframes tab of the Animation Manager) instead of a regular value.
In some cases, the keyframe properties may have been automatically disabled by the animation framework. For example, when camera keyframes are created, the properties that do not correspond to the viewer's projection type are disabled. If the keyframe was captured with a perspective projection applied to the viewer, the ortho extent property is disabled. In the same way, all the other camera properties are disabled for a keyframe if the captured viewer has an orthographic projection applied to it.
Keyframe property values can be changed to fine-tune your animation to make it look as you intend. There are numerous properties that can be changed; for example, you can change the camera target's x-coordinate to move the target to a more pleasing position.