as follows. In Section 2 we will consider the $N\to \gamma N$ transition to calculate nucleon magnetic moments. The next Section deals with the nucleon-$\Delta$-transition. We will not give the details of the calculation, but instead focus on the choice of an appropriate Lorentz basis. The sum rules for the magnetic dipole form factor $G_M(0)$ and the ratio $E2/M1$ are discussed in Section 4.

Magnetic moments of nucleons {#Proton}
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In this Section we will examine the nucleon magnetic moments. This is a classical problem that provides a test ground for many non-perturbative methods. In particular, the calculation of nucleon magnetic moments was the main objective behind the generalisation of QCD sum rules in background fields [@Ioffe:1983ju; @Balitsky:1983xk]. The results are in good agreement with experiments. In Refs.[@Braun:1988qv; @Aliev:2002ra] the magnetic moments were already calculated using LCSRs in conjunction with photon DAs. As a new element, our calculation will use, for the first time, the complete set of photon DAs[^1] and also updated non-perturbative parameters.

This simple example serves as an illustration how the calculation is carried out and allows us to test its accuracy and the dependence of the results on the various parameters. Especially, this procedure provides a 