What's generally considered finer grain between Delta and Pan-F?

Just a simple question... Is Delta 100 finer grain than Pan-F? I know that ISO ratings don't really tell the whole story...

I've debated between the two for a while. I've shot fp4+ for the last several years and have had great results in 2 1/4" and 4x5". Other than the difference in the characteristic curves I've never tried to see what the difference is as far as the graininess is concerned. Honestly, I've had such good results with Fp4+ I'm a little reluctant to shoot anything but at this point

This is helpful for me, Gents. Thank You.

Pan-F is slightly finer grained than Delta 100, but Delta 100 has slightly better resolution (and to my eye) slightly better perceived sharpness - all much of a muchness. Acros is a bit finer grained than Delta I think, but about equal with Pan-F resolution-wise. Better to pick the characteristic curve & colour sensitivity you want.