ILFORD does not test with PMK, so we don't have any times to recommend. However, the new version of Delta 400 is faster than the old version, by nearly 2/3 stop in some developers, 1/3 in all others. If you rated the old film at 250, I would guess that you will rate the new version at no less than 320, and may even get the full 400 from it.(posted 8519 days ago)David Carper ILFORD Technical Service