Resolution is how well or how small detail you can see on clarity. Personally I used to use nothing else but Leupold at least VX-3 or above or Zeiss, but being on extremely limited fixed income now I've switched to Nikon Monarch. Check out a Monarch 5 if you can. I'll bet you'll be surprised! I'd also think Vortex should be good in upgraded model if you can save up for it.