Fuji X-20 compared to Nikon D50

Depends on the lens used on the d50. If You were using a 35 or 50 mm prime wide open the nikon will be 2-3 stops better. If it was with 18-55 I would say fuji will be equal or better. Just comparing sensors the x20 will be weaker at high iso, at least a stop.

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Dimitar Ivanov