I frequently attach my iPhone to a spotting scope (using a holding adapter) to take pics and vids of birds. It's a bit of a pain to line up the optical axis of the camera with the optical axis of the scope, but once it is set, it is good to go. I've recently replaced my 6+ with an 8+ . Using the 1x lens with this setup is fine, but whenever I use the 2x lens, within 1 sec of lining up the axes, the screen goes blank. Switching to 1x then back to 2x brings up the picture, but 1 sec later it goes blank. I know the axes are lined up because for that 1 sec, everything looks fine. Any ideas what is causing this problem ? It happens for both photo and video. The 2x lens works fine in non-scope situations. I'm thinking its something in the camera app itself ?