I read an article by a crime scene technician, and he stated that the lights are more or less a scam. He recommended a product called Bloodglow. Its 2 tablets that you put in 8 oz of water and then spray it where you think blood may possibly be. It will light up the hemoglobins in the blood a blue color.
I ordered some for last year but did not get to try it out due to good blood trails. This year we had a trail that was very hard to follow and we tried it out for the first time.
It worked, but it gave false positives as well. I felt that it was best for those times when you lose blood and need a direction to go. As an example: We lost blood completely and the deer could have gone in any direction--we sprayed this stuff and all the branches lit up on some pines. Upon closer inspection we did find a very small amount of blood, so we now knew which direction the deer was headed. We ended up backing out and finding the deer the next a.m.
It can only be used at night and the darker it is the better.
You cant just walk along spraying away expecting it will lead you right to the deer, but it can be the difference maker when trailing a tough blood trail.
For $20 you get enough tablets to make several bottles, and I thought that was reasonable if it helped me find only one deer.
Genesis 27:3 Take your bow and quiver full of arrows out into the open country, and hunt some wild game.....