As I get older, I find I need more magnification for certain shots. Low/bad light and shadows are more of a problem. Being able to see the target is just harder. My lower power scopes are just not as easy to use now as in the past. In good light, the scope is cranked down but more often I'm having to turn them up. As I'm moving towards higher magnification scopes I wonder at what point a larger objective starts to really pull away from the usual 40mm and under what conditions it makes a difference. I don't presently own anything with a larger objective than 40mm. I've never noticed any difference between a 40mm and 50mm scope in the 3x9 magnification range. Does a difference start to show up at 12x? 15x?, higher? For my purposes, lets keep the discussion confined to scopes of good brands at less than $1000.00.