Originally Posted by klee
What I do know from my practical experience is you can keep increasing the resolution of a lense system to some pretty incredible limits but at the sacrifice of depth of field and thats your trade off.
There is no direct relationship between depth of field and resolution in riflescopes.
Depth of field is affected by numerous factors, most obviously if they are of fixed parallax design, adjustable objective or sidefocus in order of decreasing depth of field in general. Really good examples of each will have great resolution, poor examples will have poor resolution.
One of the sharpest scopes I've ever had (probably still the sharpest resolution-wise for the money) was an IOR 2.5-10. It was in sharp focus from just beyond the muzzle to infinity. Great glass, coatings and optical design. Huge depth of field.
One of the poorest resolution "nice" scopes I've had, a 4.5-14X Leupold, had a very shallow depth of field. That had nothing to do with its resolution, but was a result of being a side focus scope--they pretty much all have shallower depth of field; those with "good glass" and those with "mediocre glass" alike.
In short, there are trade offs for scopes with better resolution. Mostly it's $$$$. Depth of field has nothing to do with it.