Example image and manual focus identification.

<p>(A) Spread nuclear DNA from budding yeast meiosis stained with DAPI (DNA, left) and antibodies against Zip3-GFP (middle). The merged image is shown in false colour on the right. Scale bar = 2 µm. (B) Experimenter-labelled maxima (foci) of Zip3-GFP within the DNA region (determined by the experimenter). (C) Quantification of foci from the same 21 images by three different experimenters (P1 to P3). ‘Expert’ refers to scientists with previous knowledge of Zip3 or Msh4 quantification. Magenta bars represent the arithmetic mean, the black bar in the box-and-whisker plot shows the median value and all individual data points are shown as dots. Whiskers extend 1.5× of the interquartile range or to the minimum/maximum value, when these fall within 1.5× of the interquartile range.