I'll try to answer this: Firstly, fluorescence is not always measured in Log scale, one example is propidium iodide in DNA ploidy analysis. It is possible to acquire data in FSC and/or SSC switched to log in some cases, it just depends on the instrument and particles you're studying. Basically, the higher the range of something, the better the log scale works (more convenient measurement) Let's say the expression of some molecule ranges from 1000 to 3000 molecules per cell. When you plot your cell in a histogram showing the density of expression of your molecule per cell, you will have a 3 fold difference between the highest and lowest expressors; on a log scale the spread is only 3 to 3.4 (approximately) I found this quote by Doctor Schwa from The Math Forum: "On standard axes, an equal QUANTITY of change is an equal amount of space. On log axes, an equal PERCENT change is an equal amount of space. You can thus use your eyes to quickly compare percent growth or percent change, instead of having to correct for the magnitude of the data. That is, 10 and 12 will be equally far apart as 50 and 60 on log axes, because each is a 20% increase." I hope this helps, Maciej
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