One of my best research pictures was over, around or above a settlers grave (that someone or some entity attempted to dig up several years later and I rehabilitated to speck based on a picture I made of the ground around the monument), it had so many different colored orbs hovering over it that were caught on digital camera that I was literally flabbergasted. It is one of my chief research achievements photographically; and no, there is no pollen or dust that will reproduce what I caught that afternoon.
That said my sighting involved dayglow green eyeglow from Sasquatch at civil twilight. Sure I may be sensitive to blue/green doesn't take anything away from the typical red eyeshine incidents. The only blue glow I ever photographed in fog/rainy overcast daylight with was the back of a tulip poplar tree trunk base that was partially hollowed out that had an open lesion on the opposite side large enough for me to use as a "drop zone" for a sasquatch feeding station, hands could fit in and large animal likely not. I used to drop apples and a closed peanut butter jar with loosened lid in there. That "lesion" has long since totally healed over, and the picture I gained has long since been lost in a series of unfortunate backups and hard-drive failures. That said the area was a hot-zone of synchronicities, many of which shook me to my core. Not skinwalker stuff, but running a close second.