Sorry, but I need to res this.
Camouflage really reads like it just
takes effect without any resistance whatsoever.
As a Physical, Single Sense, Realistic spell, Physical Camouflage is also resisted the same way as Improved Invisibility. The benefits are also a -1 to opposed Perception rolls based on the spellcasting's net hits, so the penalty can vary greatly from NPC to NPC.
No, it's 1 die per
hit, not net hit.
Between the drain code, the description / effect, and the fact that it uses hits rather than net hits, everything about it suggests that the spell just happens, without any chance for a resist. And in fact, that reading is the only way the spell(s) makes sense, given the comparison to Invisibility(s).
In fact, it reads very much like the Armor spell, and no one would suggest
that can be resisted, even if cast on a suicidal subject.
Maybe it's just a case of terrible cgl writing / editing, but, unlike most (all?) other spells that can be resisted, Camouflage avoids any mention of "failing to resist," object resistance or net hits. Every other spell surrounding it makes a point of including such verbiage, but Camouflage alone only says "1 die
per hit" instead.