I recently watched a video by Ian Steppler where he did thermal imaging of the hives inside his shed. He was able to tell the difference between the dead colonies and those that were alive, but had moved up in the hive. Since he didn't mention the model of the unit and I didn't detect a model number on it in the video, and of coarse his mailbox is full, I thought I'd ask the question here as to which FLUKE Thermal Imaging unit is most used by beekeepers for accessing the mortality rate on their hives? A visit to the FLUKE website showed a large number of units that fell under the professional grade as well as the performance grade units with with as many different prices as units! I would like to check my outside wintered hives periodically.