Given a morphism $f:X\rightarrow Y$ between smooth complex varieties, one can define functors from the bounded derived category with holonomic cohomology on $Y$ to the same category on $X$. The easiest one is $Lf^{*}$ which can be obtained by putting a $D$-module structure on the inverse image of $\mathcal O$-modules and deriving it. From this one can get two more functors:

 - $f^!:=D \circ Lf^{*} \circ D$, where $D$ is the duality functor and
 - $f^{\dagger}:=Lf^{*}[dim X-dim Y] $

Now my question is, under what conditions are these two isomorphic?