Eric, thank you. I was a bit disappointed also at the grain, and my Pan-F results have been inconsistent, often with blocked shadows(I use HC110 or Rodinol) and surprising grain. Haven't figured it out - possibly a resizing artifact?
grahamp, since I aimed low to shoot, there was little above the horizon remaining to play with. However, I do think you have a point, and re-scanned with the remaining horizon present: looks better, thanks.