The Color heliar is the best lens choice in general. The Apo Lanthar would be nice but the prices are silly. The eyepiece is small, no doubt, but its' usable as long as it's clean. This is easily the best/most elegantly designed and built 6x9 folder, you can tell these were top of the line at the time (and still.) I've thought about selling mine but every time I use it I remember why I like it so much...