Another vote for 50mm - it's just such a versatile focal length, and as Scott says, there's not much sense in doubling up with the same focal length as the X100. Between the 50/1.2 and pushing your Tri-X, shooting at night becomes very do-able.
I have a roll of pushed Tri-X on the go at the moment ready to head to the UK.
I've also finished scanning my backlog of photographs from September to early December. I'm going to switch to a more professional lab and have them handle my scanning from now on, and probably sell the V600 on now that it has fulfilled its duties of scanning the dozen or so rolls I had racked up.
I still need to go through and do dust removal on half my scans. This is from a roll in late November. I love these vans that you see in all rural Spanish towns, nipping up and down through tight, cobbled streets or up goat tracks at surprising speed. I was out my bike photographing the greenhouses and the rural landscape, and when I saw this Pueblo Van it made my day.
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