I've slightly reformulated the emulsion to remove some lingering base fog and also make the highlights a bit punchier. So batch 42 was a test batch to do this stuff. I characterized this batch to baseline the emulsion recipe going forward.
Base fog: 0.09
Development was per box recommendations, except developer temperature was 22C. I would expect contrast to be slightly lower at 20C.
I really like how plates from this batch look, as demonstrated by Portrait Test Victim #3 taken with a 150mm f/4.5 Voigtlander Heliar onto 4x5. Metering was at ASA 2 on a gray card next to his face.