10 initial inversions first 30 seconds. 4x/minute after.
Recipes & dev times using Film Ilford HP5+ 400
Ilford HP5+ 400 in Kodak D-76 1+1
12 minutes, 15 seconds at 20°C/68.0°F
Ilford HP5+ 400 in Kodak D-76 1+1
13 minutes at 20°C/68.0°F
Ilford HP5+ 400 at 640 in Kodak D-76 1:1
15 minutes at 20°C/68.0°F