Most of my cameras have been SLR or had a built in rangefinder. As a mechanically inclined sort, I find I do pretty well at estimating distances. My one session of slight panic was doing some flash photography outdoors at a wedding where the wooded location resulted in near total darkness. No matter how good my estimates were, I had one heck of a time reading the numbers on the focus scale to set it! The problem never crossed my mind until I was faced with it. I was not an official photographer fortunately.