$\theta_{min}$ scales approximately linearly as the ratio of the flux to the RMS sky noise. We have looked at this scaling in a sample of galaxies detected with ACS (and which we describe in greater detail below), each of which was imaged in 4 frames. Prior to stacking of these frames, we found that $\theta_{min} = 0.75$ produced low $\chi^2$ and convergence with small values of $n_{max}$. After stacking, $\theta_{min}=0.4$ was required. This makes sense, since the noisier our image, the more prone we might otherwise be to fitting complex polynomials to what is, essentially, noise.

Roughly, the processing time for a decomposition scales as $\theta_{max}^4$, as $\theta_{max}$ determines both the postage stamp size and the maximum order of the shapelet decomposition. Due to the high resolution of our images, we encountered a number of objects for which $n_{max}$ was so large that the decomposition time became prohibitive. We opted to re-grid images with $n_{max} > 50$ into larger pixels by taking the mean of the pixel values in square bins, the size of which is determined by $binsize = n_{max}/50$. This number was rounded up for objects with $50 < n_{max} \le 75$.

A flexion measurement is then carried 