I pretty much followed D. Ross's formulas with some changes to suit my own workflow and availability of materials. I omitted the KI because I wanted to see what the effect was. And since Everclear is not available in NYS, I used Bacardi 151, ummm rum flavored emulsion.

I test print shows almost all the steps on a Stouffer step wedge, a very long scale; interesting! Developer was Ansco 130 1:1 for 2 minutes. I am going to experiment by adding KBr to get the contrast up. Paper is Arches HP, coated with a blade I constructed out of 1/2" plexi-glass.

The blade is shaped like a trough inside and holds the paper flat just ahead of the stainless blade. It was surfaced on a thick plate of glass with 220 grit sandpaper and water; it's very flat. The blade is a 6" stainless ruler (good enough for now) and is clamped in the slots you see in the image. Two stainless screws squeeze the slots closed to hold the blade.

I need to make the blade out of 1" plexi so it will hold more emulsion. Right now 10 mL is the max.

Also attached is a quick graph of its curve.