The grainy ones are the ones shot on the cheap Arista brand film. I actually really love the colours that the film produced, but it's quite grainy for an ISO 100 film. Thanks a lot for your kind words, unfortuanately I don't feel I did a very good job capturing the scale of these machines. When I first went up to one and looked at it I felt dizzy from the sheer enormity of it... WOW.