<p>1/ MC lenses will show a cyan/magenta layer as you tilt the lens to and from under sunlight. If you see amber/blue, the lens is single coated.<br>
2/ For the 1.4/50 lens, the MC versions start at SN 1mm.<br>
3/ The MC lenses give the best colour saturation and contrast. The 1.4/50 appears to be configured as a Sonnar, and gives smooth bokeh. The 1.8/50 appears to be configured as a Planar, and gives max sharpness but less smooth bokeh. Both are superb for optics and mechanics.<br>
4/ almost all OM Zuikos are excellent for the Sony A7 series. </p>
