First, let be a set with , and write for the orthogonal projection of into the line spanned by . For , write where is the -covering number of the set . It is well-known – and essentially due to R. Kaufman – that $N(E_{s},\delta) \lessapprox \delta^{-s}$ N(E_{s},r) \lessapprox \min\left{\delta^{-s}\left(\frac{\delta}{r}\right)^{1/2},r^{-1}\right}, \quad \delta \leq r \leq 1.I construct examples showing that the exponents in the bound are sharp for $\delta \leq r \leq \delta^{s}$. The second theorem concerns projections of $1$-Ahlfors-David regular sets. Let $A \geq 1$ and $1/2 \leq s < 1$ be given. I prove that, for $p = p(A,s) \in \mathbb{N}$ large enough, the finite set of unit vectors $S_{p} := \{e^{2\pi i k/p} : 0 \leq k < p\}$ has the following property. If $K \subset B(0,1)$ is non-empty and $1$-Ahlfors-David regular with regularity constant at most $A$, then\frac{1}{p} \sum_{e \in S_{p}} N(\pi_{e}(K),\delta) \geq \delta^{-s}$\delta > 0\overline{\dim}{} \pi{e}(K) \geq se \in S_{p}$.

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