Is black shading affected by :

- body temperature of the R1 (cold or warm) ?
- ASA setting (should the R1 be set to the 'target ASA' or will any setting do ?) ie: is shoting at 1280ASA should on do a black shading at that setting rather than 320ASA ?
- any un-documented 'other' factors ?

Always been curious but keep forgetting to ask ;-)