If there was a ghost mode it would have to bump the ISO to "HI" setting in order to capture those fleeting wisps of energy.
Yes if you consider multi-dimensionality (beyond four dimensions), then ghosts would be pretty mundane and everyday sorts of entities. Whether their energy can be captured by a digital camera that itself is only a 3D entity is another question. We take pictures of 3D objects and view them in 2D. A 4D object casts a 3D shadow, which we could look at in 2D. So who knows...
They've managed to image light moving through space (high speed imaging) so perhaps in time the resolution will be there for resolving all kinds of energy patterns.