@jharr asked, 'john, are you thinking of range focusing?'
Yes, focusing by scale should be sufficient. Remember, this is a non magnified image so DOF restrictions are loosened. With a negative that is going to be enlarged you have to select a suitable minimum out of focus spot for depth of field calculations because the original will be magnified when enlarged. With instant pictures, you don't generally enlarge them, they are just at 1X so focusing by estimating the distance and setting it on the scale should work fine, depth of field will cover slight errors in focus settings. In fact, 'zone' focusing should work fine with such a small print.
One problem I see with this camera is that the lens they are using is 110mm. That is really too long/narrow angle for general picture taking (but nice for portraits). A 75mm lens would offer a somewhat more useful angle of view for more general picture taking. I'm thinking the reason they have selected so long a lens is because a simple, single element lens does not have the coverage needed, there would be a lot of fall off (dark corners) with shorter single element lenses. At least, that's my best guess on that.
