Guy on the left has chaps on so I'm guessing he would be the operator and the guy in the middle looks like he has communication equipment on his back. The kid on the right is super scrawny and my guess is it's one of their sons and his whole purpose is to carry the gear needed for operating a chainsaw. He should have chainsaw oil on him/her but I don't see any. These three would be fairly easy to identify in another photo just based on their gear and bodies sizes.