Hands-on with Fujifilm’s new XF 16-55mm F2.8 R LM WR lens

* Bigger Sensors will have better SNR / High ISO performance (but that’s all electronics, nothing to do with optics).

* Bigger sensor will produce more heat inside the camera body, so will be more difficult to design for applications, where high readout is required, like video, higher burst rate, electronic shutter etc.

* And less significant factor (subjective) is the Dof will be shallower on FF which can be advantage or disadvantage depending on your applications. Portraits (maybe) advantage, in Landscape (arguably) disadvantage (longer exposure).

* Diffraction and Hyperfocal distance comes at very smaller apperture values on FF (longer exposure).

* Also to get better results for sharpness, CA, or vignetting you need to stop down much smaller than the the biggest aperture values.

and the list may go on further!..

but the main point is ..
Apperture is just the divider to the lens focal length!
So it will remain same.

Source Article from http://www.dpreview.com/articles/2652979930/hands-on-with-fujifilm-s-new-xf-16-55mm-f2-8-r-lm-wr-lens