Post-Script: Today I took a field trip up the Turquoise Trail to the former mining town of Madrid, NM, with my handmade 8x10 box camera, and exposed six of these Harman Direct Positive Prints. It's been a while since I've worked with it, and ended up over-exposing most of them in the bright sun. I had forgotten that in shade it's okay to use ISO 1.6, but in bright sun one should rate its speed around ISO 3-6. Live and learn. I do have copious notes made with each print I've created, but they're not in a convenient format, and so I didn't refer to past experience as I should.
But the bright side is that we now have a ready supply of this paper to work with, and so I hope to work the bugs out of my process soon.
The top photo was made under soft, indirect daylight at ISO 1.6. One unique attribute of this paper is that, just like tintypes, the image is reversed left-to-right.