However, it didn't do a great job of finding a blood trail. Since Matt's deer was shot when it was 60 degrees we assumed the warm temperature may be a factor.  So we tried it again on blood trails in November and December and achieved the same result.  It seems that drops and spatter cool down quickly and the FLIR provided little assistance for spotting blood. Pools were a different story.  They stood out better within 30 minutes of the shot.  Unless you get down immediately (and we all know that's not smart) I wouldn't bother looking for blood with a thermal unit. Its best use is locating the animal itself.

We used the unit on four recoveries in 2012. It performed extremely well on three of them. It did not do well on one particular recovery.  I had made a poor shot on a nice buck. The liver hit deer ran to an area thick with fallen trees and brush piles.  It was late afternoon and everything was glowing in the FLIR's viewfinder.   We knew the deer was bedded somewhere in that tangle but there was not enough temperature differential to pick it out. I was a bit disappointed.  This was the first recovery where I needed assistance from the unit (the other three hits were slam dunks).  We got the deer, but the FLIR played no role in that recovery.

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Just wondering if you have a deer that's been hit and leaving a blood trail, how long afterward is that blood trail going to be apparent through a thermal imager?

I recently picked up a ThermApp. Yesterday someone was telling me about hitting a deer and they lost the trail. I realize it's way too late now but I was wondering if they