Originally Posted by Daveh
Originally Posted by TBS
I prefer the A.O. to the side parallax adjustment. I think the A.O. has a better depth of field


I didn't read all the posts but this is it for me. Depth of field. The side focus scopes I have owned were the newer Leupolds, Zeiss and Nikon.

To me the best side focus was the Nikon Buckmaster.......

I have no clue to all the technical reasons just I know what I saw....

Dave

I think Nikon uses a narrower field stop to enhance DOF on their side focus scopes. This gives that "tunnel vision" vignetting effect found in at least my Buckmaster 4.5-14x, and reduces FOV a little bit, but increases DOF across all magnifications (most notably on high magnification). I'm not sure if they do this in the non-SF Buckmaster scopes, which is where you'd really need a wide DOF, since parallax is fixed at one range. I suppose it's to allow the focus to be clear over a wider range of side adjustment?