......... so Donald and Henning can I ask what you have to do in terms of exposure with CMS 20 II that is not required with say TMax or D100 and how difficult is it to achieve a full range of tones?
Thanks
pentaxuser
For the combination of highest sensitivity and best tonality / best characteristic curve my clear recommendation is to use the dedicated ADOX Adotech IV developer. The CMS 20 II is a "highest-performance-film" concerning resolution, sharpness and fineness of grain. It's like a formula 1 race car: If you are making races with it you will use the best material, the best tires, the best mechanics etc. to achieve the full performance.
No one would use the weels and tires of a VW Golf for a formula 1 race car......

. And using other standard developers for CMS 20 II is like that

.
In projection I have enlarged this film in 35mm to a width of 5 meters. I put my nose on the screen and could see the finest details! This film has no limits in enlarging. Under a miscroscope with 100x enlarging factor (2.4 meters x 3.6 meters) its absolutely fascinating how sharp and extremely high resolving this film is.
Well, after school and before studying at university I worked in the car industry. At that time all spare part lists were archived on microfilm. When you have seen thousands of parts on only one small sheet of microfiche, you know what extreme resolving power microfilm has

.
With Adotech IV you can use this film in a range from EI 3/6° to 25/15°. This film-developer combination is very flexible if you know the Zone system and proper developing. With 3/6° and 6/9° you get a more linear charactaristic curve. With 12/12° and 20/14° you get a more S-shaped curve, but in a quite unproblematic way: Very good mid-tone and highlight detail, and less shadow detail in Zone I, II and III. But there is a simple trick to get the shadow detail: Use a fill-in flash and by that give the shadows just so much light that they get 1-2 Zones higher.
Best regards,
Henning