Better artillery effect on observed targets?

[JacquesDeLalaing]

Is the effect of artillery better if the target is observed by other units in the chain of command of the artillery unit? Or is blind fire on supposed enemy positions just as effective as fire directed by spotters?
There is nothing in the manual on that.

[IronMikeGolf]

Observed fire is better. Blind fire on high echelon HQs might give the impression that not having an observer matters, but that's an effect of lots of soft targets in the hex and usually larger caliber (150mm+ class). 120mm class and below on light armor unobserved usually won't give a casualty. You still get a Readiness decrement, of course.