I have been considering the Dw-4 finder for the F-3 since it would provide a 6x magnification for macro photography, making it easier to focus. Being an expensive accessory it's hard to justify the expense of it. I've been thinking about using a cheap higher magnification loupe (22x for instance) for checking the focus directly over the camera's screen. Should this procedure work? It's like it is done with large format cameras, isn't it? I understand I won't have the view of the whole frame, but I would just check the focus and easily could take the loupe out for checking the composition. This won't be as confortable to do as with a dedicated finder, but it won't be nearly as expensive either. Peak even make a loupe with a rubber cup that should avoid any damage to the screen. What about this idea?