- Back in the heyday of SX-70 auras, a guy named Don Danylyk posted a Polaroid of an old house where the photo has the classic "Polaroid flare." They then metal detected the house and discovered a small cache of coins behind a brick in the fireplace. He also showed other Polaroid flare examples where nothing was found.
- Despite the utter bogosity of LRLs, I know of a case where an LRL user actually located a cache of silver coins. How could that happen if LRLs are bogus? Well, he used the LRL a whole lot and followed up every LRL-detected spot with a metal detector until he eventually found something.
These are cases of the classic "Blind Squirrel" scenario. Do it enough and you might eventually get a hit, regardless of the validity of the process. Unfortunately, an otherwise random discovery can grossly skew one's perception of what is going on, leading them down a long road of wasted time. A better approach is to devise tests to see what actually works and what doesn't. Ferinstance, if auras are real, can you bury a test target and get repeatable results?
I take it you are only attempting aura photography at these particular sites, so it makes sense that when you manage to capture an anomaly it is always at one of these sites. It's a self-fulfilling prophesy. OTOH, if the anomalies are caused by the camera itself, you could get these anomalies anywhere. That might be a worthy experiment.