Originally posted by chrisrussell So essentially when I shoot with my FA 50mm f1.4 on my Pentax K-x - I'm actually shooing with a tighter 75mm equivalent but with all the bells and whistles of a 50mm.
Purchasing a modern 50mm which works with smaller censors will yield a 'wider' photographic view which will actually be 50mm?
No,
I believe you missed the point.
50mm is 50mm and nothing changes between old (film) and new (digital ASP-C), you will have the same field of view on your digital camera with any 50mm, old or new. That is why I provided you with the short answer above. Your FA50 will work identically to any digital 50mm lens.
Field of view on any camera is a function of focal length and sensor size. Since focal length is a physical property of a lens (and is camera independant), and your sensor size is a physical property of your camera (and lens independant), simply changing one 50mm lens for another will not alter AT ALL your field of view.