}\tilde{\beta}=0$. Define $\tilde{f}:S\oplus Q\rightarrow E$ to be $$\tilde{f}=f\circ \left(\begin{split}   &Id_{S}  &\gamma \\   &0  &Id_{Q} \end{split}\right),$$ then $$\tilde{f}^{*}(D_{E})=\left(\begin{split}   &D_{S}  &\tilde{\beta} \\   &0  &D_{Q} \end{split}\right)