I use to use a $2000 unit for viewing at night, had a 6 power lens. Just one problem with it, if a coyote was in a dirt field at around 300 yrds it was very hard to see, no contrast.
I sold the unit and now I use just the NightForce light units that mount on your rifle or shotgun. By carrying a 12 volt-12 amp battery this combination works much better in finding the coyotes then the Night vision viewer. I can locate eyes to 400 yards plus with out much problem with the red lens and have taken coyotes out to 250 or so yards.