@tomnorthfilm Although we're not yet home, I was time-wasting on my phone while waiting for ThingsTo Happen, and checked the MDC app. It gives a time for Cinestill BWXX in HC-110 1+47 at 20C as 8 minutes, which I'm pretty sure is used as my base for the REFLX DoubleX (less 15% for the Rondinax).