I've been annoyed by and dissatisfied with how J. Lane Dry plates lose so much speed in wintertime, so I've been working almost non-stop over the past two weeks (and at a less hectic pace before then) to refine the emulsion formula so that the plates give denser negatives in the winter when metered at ASA 2. Essentially this means I've kicked the speed / contrast up while retaining the extremely fine grain. To give you an idea of how much testing, I have a stack of about 200 plates worth of Stouffer Step Wedges that I've developed over the past month or so testing and retesting tweaks and additions to get the emulsion right. (Those will be cleaned and repurposed for future orders, in case you were wondering).
Starting with Batch 37 (printed on the back label of each box), you'll find a significant increase in speed and contrast. I actually overshot the mark a bit with Batch 37 and it might be a bit *too* fast for ASA 2 metering this time of year (not that I think anybody would complain), so I'll dial back the speed / contrast a stop or so for batch 38. I actually considered dumping batch 37 but to be honest I've been making and tossing so many emulsion batches and developing so many plates that I'm a bit burned out and would rather just get this out into the world since it has such nice grain and tonality.
I also saw that the swirlies were starting to rear their ugly head again but I think I beat that down with additional stabilizer.. we'll see if that does the trick. That seemed to have helped, but time will tell.
The first few boxes of batch 37 will be going to Bostick & Sullivan, who ordered them to restock 4x5 if you're interested in trying some out. I'll be filling my own orders from existing inventory, so it'll be a bit before the new emulsion is cycled through my store. Or, after the short vacation we're going on I might just say f' it and strip all the emulsion off the plates in inventory and recoat them.
Now back to my regularly-scheduled refinement of Speed Plates emulsion and the dry plate holder prototype testing. :)