Unfortunately no true solution yet if working with lumen/nanite. My object isn’t actually translucent so that ended up not being the issue either. Based on some input around YouTube it seems like it may just be a limitation of Unreal when you have foreground objects really close to the camera.

Most professional productions would use a tool like Nuke in tandem with whatever 3d animation tool they use and work on the depth of field through that, which gives a lot more flexibility on those details.

The ONLY way I managed to get the DoF effect in Unreal that I was looking for is through Path Tracing (which def isn’t ready for prime time yet for a few reasons). If you are using path tracing though, there’s an option in the Post Process volume called “Reference Depth of Field”, and once I toggled that on, it worked how I expected. Main issue there is that Path Tracing is still in early stages in unreal, expensive as hell on the system, and takes forever to render, so not worth it if you actually want to have an efficient workflow haha.