Low light SLR
In addition to what the guys said, you need a "good" low light sensor to produce quality images with the least possible noise and much details and among your chosen bodies the D7100 is a good compromise unless you wanna spend a fortune on a top end FF body and a lens.
|big gourd by rok urankar|
|crashing waves-1 by stickpointed|
from The Wild Rugged Coast
|'Red 18' by Private Custard|