Somehow I hadn’t noted Adox before, a German company that makes several films (Scala, CHS 100, CMS 20II, and Silvermax). They have a new superpanchromatic black and white film called HR-50.
HR-50 has a resolution of 280 lp/mm and an ISO of 50 and an extended spectrum that allows it to be used as a near infrared film.
Meanwhile, their older CMS 20 II film is also a high resolution one (800 l/mm, not lp), claimed to be the highest resolving in the world, with particularly fine grain. ISO is 20, though if used for high contrast use you would bump that up. If used with a low contrast developer, the new film can be exposed between ASA 3 and 6 (Adox uses the older ASA values in their product notes).
Note that CMS 20 II has clear reciprocity failure outside the 1 second to 1/1000 second range, so you will need to adjust exposure for long or fast shutter speeds.
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