Even at ISO 100, I often end up applying fairly aggressive noise reduction (nr) when I intend to zoomin -
I don't like to go higher than 640 at worst with my D7K if the light is poor (like cities at night). Brighter light is better though.
Features of the D400...... "Native" ISO of 12,800 would be nice
On the one hand, some are getting noise at ISO 100 ( on a D800)
others are hoping for 12,800 on a dx camera
I have D800 and are happy shooting most things up ISO 3200 most of the time I shoot with AUTO ISO with no ISO limit for landscapes, were I need dynamic range and color fidelity, I prefer ISO 100 I always shoot RAW and I nearly always do bit of Fiddling with LR in post
So what are preferences? and why do think people are getting noise at ISO 100