I'm considering trying Pyrocat-HD for negatives intended for printing in salted paper and perhaps albumen and VDB as well. These processes require a negative developed to a higher Contrast Index than most other processes. On the unblinkingeye.com site, Sandy King recommends a CI of around .90 to 1.0 for negatives intended for salted paper. The CI curves posted at that site for various films never go that high though and are for negatives developed in rotary processors using the 2:2:100 mix. I intend to try Pyrocat-HD with Ilford HP5+ and use tray development. I want to standardize on HP5+ since it is available in 5x7, 8x20, and 11x14 formats unlike some other films tested at the site. As a result, I have a couple questions.
First, I'm assumming the rotary process times are approximately 15% shorter than tray times due to the more vigorous agitation. If I'm reading the CI charts correctly, it looks like HP5+ might hit a CI of .95 somewhere around 25 minutes @ 72F using a rotary process. Assuming this is correct, I'm thinking a time of 29-30 minutes @ 72F might produce the .95 CI using tray development and constant agitation. Does that sound about right to experienced users?
Second, since that time is very long, is there a quicker way to produce the high CI? Can the developer be used hotter or in greater concentration, say 4:4:100, to shorten the time without suffering any ill effects? Anyone have recommendations?
Third, it appears that Berrger BPF 200, another film available in all the formats I want to use, never gets beyond a CI of .90 or so even with extended development. What's up with that? I've only ever seen one other film that didn't respond like that to extended development and that was the old chromogenic XP1 film which only increased fbf after a certain point w/o a further change in contrast. Is that what is happening with the BPF-200?
Thanks for any info.