All caps you buy are low ESR, high ESR caps are completely different, like when your measuring capacitance out of random things.
like when your conducting a whole heap of home made semiconductor mush, when you get your series resistance.
This post is nonsense. Capacitors are not intentionally manufactured with high electrical series resistance (ESR). High ESR can be caused by age, method of lead attachment, and the technology used to establish an insulating layer between the two capacitor electrodes.
In general, electrolytic capacitors DO have higher ESR than non-electrolytic capacitors that use paper, glass, plastic film, mica, vacuum, or ceramics for insulation between the two capacitor plates before the external electrodes are attached. The ESR of electrolytic capacitors increases as a function of frequency, which is why power supply by-pass or "filter" capacitors often consist of an electrolytic capacitor wired in parallel with another type of capacitor with a known, lower, ESR.
Special "low ESR" electrolytic capacitors, as
@Harald Kapp mentioned in his post #5, are often used to reduce the "ripple current" in power supplies because this current heats the capacitor and can lead to early failure of the electrolytic dielectric insulation.
And just what, exactly, is "a whole heap of home made semiconductor mush?" It doesn't seem to correspond to any
definition of mush that I can find after a quick search on the Internet. Most respondents, at least those whose posts I consider valid, will upload comments that are both relevant and trustworthy. Your posts seldom satisfy either criteria.