Thanks everyone for the suggestions and comments!
I tried increasing agitation to 4 1s inversion cycles every 30s per the SP-445 instructions. The results were odd -- generally better for 3 of the 4 sheets (no artifacts; better contrast) but very strong artifacts of the tank holder on the 4th sheet (below)
Next I will try Mick Fagan's advice of gentler inversion with the protocol of "invert three times, with the last inversion completed at 40 seconds." I would be appreciative if anyone has thought on whether it is agitation during development or stop that is messing me up.
Bookmarks