tly by <a class="reference internal" href="BSHelp11-2-3.html#d-differential-parameters"><span class="std std-ref">differentiation</span></a> this can be quite inaccurate for low resolution detectors such as 2D arrays and the recommended method is to fit a sigmoid or Hill function to the penumbra data and determine the inflection point of the function.</p>
<p>This is described under <a class="reference internal" href="BSHelp11-2-4.html#inflection-point-parameters"><span class="std std-ref">Inflection Point P