Jhn I never noticed any focus change when I switched from 1X to 2X on my DR6. I use my DR6 on my D700 and D200. I bought an adapter on eBay years ago that just screws on the end of the DR6 to adapt it to the round eyepiece. It works great. If you search this forum, you will most likely come up with the post where I put all the details on where I bought it as this question has been asked before.