Dual Focal Plane Scope ,

Pat. - only ones I've ever seen (I'm sure I've not seen them all) have been geared toward the AR platforms due to the desire to enagage CQB and quickly move out to longer ranges. I have used them on various PB and they are def effective for their intended design. Generally the SFP part results in almost a red dot approach and the FFP part a mil based ret.

only downside as it pertains to airgunning is that all examples I've seen have set parallax generally at 100yards or meters. This concept could certainly be leveraged to make a cool airgun oriented scope. Think SFP low power for up the tree close squirrel shooting and the next shot is a 98 yard shot at another squirrel sitting on a dead log on the ground using FFP and higher magnification.

cool concept

 
The Weaver Tacticals for the AR platform are great values with solid build and clear optics along with decent turrets. They're made for you to zero and cap off while using the reticle for ranging and adjusting fire downrange. I have their 1-5X with CIRT reticle and it performs very well for close work out to intermediate range, a solid chunk of scope it is...heck, the other Weaver scopes on my hunting rifles are just as clear and perform excellent. We are talking about their scopes made in Japan with decent lenses.