NOTE: These techniques were developed based on a zero deviation assumption. These techniques can be used with deep space probes but the deviations make it very impractical. The best time to use these would be when you are narrowing down the site with core scanner probes and after reducing your scan radii, you only get a ring or dots (This because the deviations are much smaller).
Get a decent fix using 3 probes: Once you have 3 probes in space, you will have 2 dots as your result. If you then move one of the 3 probes and scan again, you will get 2 dots again but one of the dots will have shifted. The dot that didn't shift is where the site is.
Tiree-Catryes planar method for 3 probes Once you have the ring with 2 probes, Drop a third probe and move all three probes into the plane of the ring. This should make the two dots right on top of each other.
Get a decent fix using 2 probes: Once you have 2 probes in space, you will have a ring as your result. If you then move one of the 2 probes and scan again, you will get another ring but shifted. The site has to be on both rings so remember where the first ring was and look for the spot where the second ring goes through the same spot. The site will be there.
Get a decent fix using 1 probe: Theoretically possible but what a headache. This is however your last resort, when everything fail this will let you know where the site is with a very good degree of precision. You'd have to remember the signature strength of the site, move the probe, scan again, and look whether the scan strength increased or decreased. Good luck with that though.
Taken from the Advanced Scanning Tutorial - EvE Online Wikipedia
wiki.eveonline.com Apocryphea exploration
Apocrypha Scanning Tutorial
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