In the old days, before Pitch F/X, you could get readings on both. Technically you’d get a speed out of the hand from one type of radar gun and as it crossed the plate with another. Scouts referred to the two guns as “the fast gun” and “the slow gun.” Both were in-accurate measurements of speed though, depending on the aim of the person with the gun and the accuracy of the gun itself.
Now, with Pitch F/X being the recognized authority for pitch velocities for many years, and with Stat Cast capturing even more information and now taking over as the standard, things have changed. Its explained well here but the summary is this:
- Pitch F/X captures the velocity at either 50 or 55 feet from home plate (sources differ as to the exact spot and it may have changed over time), so not out of the hand but slightly afterwards to get a consistent viewpoint irrespective of the pitcher (whose height’s vary and whose release points are all slightly different in terms of distance from home).
- Stat Cast captures the fastest measurement of the ball at any point from the point it leaves the pitcher’s hand to the moment it crosses the plate.
So, obviously the fastest point should be just after the pitcher releases it. And thus, under stat cast suddenly pitchers are “gaining” reported velocity on their pitches from just last year. This change is reported well at this Fangraphs link from early this season.
