I finally purchased and tried some PMK Pyro. Not sure where or when I first read about pyro developers, but I had promised myself (along with buying and mixing up a new batch of Diafine) that once I moved, I would purchase some pyro as well. Not sure why I decided on the PMK--it was between that or the WD2D+. Based on what I had read about the nastiness of this stuff (toxic-city), I had hoped to get the liquid version and avoid inhaling more of the stuff than I had to. And, of course, rubber gloves were a must. I've not done a whole lot of research on pyro--just enough to know: 1. that the stuff is pretty toxic; 2. that the solution stains the negatives--kinda like a caffenol dev, and 3. that there is debate over whether or not the pyro look is all that different from the look/s that can be had using other b/w developers.
I ordered the liquid pmk pyro from freestyle photo. For 32.49 I got enough of the A and B solutions for 50 liters. Importantly, with this one shot developer, you mix it when you need it and only as much as you need. Though the directions say that you should mix at least 500 ml of solution. Like Rodinal (or more specifically, like doing stand developing with Rodinal), you don't use much of the solutions at a time. It's 1 part A, 2 parts B for every 100 parts water. Unless, as I understand it, you are developing infrared film--in that case, it's 2:4:100. Still, it's easy to see that the solutions will last a good long time.
To be fair, it's a fairly time consuming and high-maintenance process. Especially when compared with Rodinal stands (low maintenance to the max) or color developing with Tetenal C41 (a fairly speedy dev process). Never mind that you're wearing (or should be wearing) gloves and a face mask and glasses or googles during the dev process. I couldn't find an exact dev time for the expired efke kb 400 film I was developing, so I went with 15 minutes, averaging out the times given for Ilford HP5+ and Agfa APX 400. The tricky part is that you have to do vigorous inversion agitation every 15 seconds (yikes) for the whole development time. Took some getting used to. . .though that said, I never invert. Too messy/leaky. My tank came with an agitator wand, so I use that instead. After the film has had its water stop bath and fixer, you put it back into the spent developer for another 2 minutes, agitating every 30 seconds. After that it's a 20-30 minute wash. It is, as I understand it, during the wash that the stain increases. So in addition to being a toxic process (at least to start. . .as I understand it, the chemicals weaken throughout the process, hence the reason why you mix only as much as you need when when you need it), it's not a process that is given to conserving water.
The jury (well, my jury, anyway) is still out on the results I've gotten from pmk pyro. I love the look of these images, the richness of the blacks, the grays, etc. but I'm not sure that I notice a huge, huge, difference here. Or maybe I just like the images themselves, the subject matter, etc. By the by, all the images featured here were taken with the Canon AE1 Program. Of late, it's really been my go-to camera--especially for all the "interiors" shots I've been doing lately.
I would really like to try infrared with pmk pyro. From what little I've read and seen, it's said to decrease a bit of the infrared effect but deepens shadows. Or something like that. In the end, I'm glad that I tried this, and will likely try it again. It definitely won't be my go-to process in that way Diafine or Rodinal stands are, but I think I like the results. Maybe even a lot.