Increase draw distance of distance field for distance blur?

I’m trying to use gaussianDOF to give objects in the distance a nice blur effect.

This works, except I seem to have an issue where it does not blur objects for a short distance in front of me, then it progressively starts blurring, then it does not apply any blur at all.

It seems like the distance field that is generated for the environment stops getting generated at some point. In this level, you can see a very long ways.

I have attached a screenshot showing what I mean, along with another screenshot showing my DOF settings. Any ideas for how I can make it blur consistently from not blurry in front to blurry in back?

FWIW, I turned out to have post process settings on the player camera and it defined a Sky Distance parameter, which was closer than I wanted the farthest plane to end, hence giving me the problems I was having. So, the culprit was user error.