When using the Live view/Movie mode on the 5D mkII, I started with the Letus Hawk viewfinder . I wear glasses but I had to remove them to get my eye closer to the eye piece. With or without glasses I could not focus the lens with the diopter. The Zacuto Z-Finder 2.5X has a larger eye cup so I can leave my glasses on which helps when working the buttons and menus. It also comes with 3 extension rings that fit around the Z-Finder between it and the LCD monitor. If you rack the diopter all the way and still can’t get a sharp focus then add the rings. I used 2 for a perfectly sharp image. Achieving sharp focus is easier with the Marshall 5″ monitor. I’ll get to that in a later blog.