Perceptol (or Microdol-X) used full strength will cost a full stop of speed, so Tri-X at EI 200 wouldn't be a bad idea. If you dilute these developers speed, sharpness and grain increase. 1+1 or 1+2 are good compromises. I get great results with Tmax 400 at EI 800 with Microphen diluted 1+2.(posted 8193 days ago)