Nikkor PC (perspective control) lens 35mm f2.8. I found one of these on e-bay two years ago and I've been using it the last few weeks on my nikkormat for my lunch hour photo excursions in downtown. The PC Nikkor allowed the front lens elements to shift in one of twelve directions by turning a shift knob. Primary use was for architectural photography to compensate for perspective distortion but it could also be used for panoramic work. It was the first and in its day only 35mm lens that allowed such shifting giving an SLR some of the capabilities of a large format view camera. Over the viewfinder I have a flip up magnifying viewfinder that helps me with critical focusing.