Short of test driving all of them, is there a guideline regarding choice of focal lengths for TS lenses. What are the typical needs met by 17mm, 24mm, 45mm, and 90mm TS lenses? Does it differ is a FF, APS-H, or APS-C body is used? I just shot the 17mm and it seems to be better suited for large subjects and shooting from lower elevations. I will shoot the 24mm next.