OLL50 (L shape)

R’ F R2 B’ R2′ F’ R2 B R’ (L shape at upper left portion of U-face)

This has 3 half turns (R2/R2′), and F/B’/F’/B appear alternately before and after them, so it is very rhythmical.

Finger technic: B’ by left index finger, pushing ULB piece, F’ by the same finger, pulling UFL piece. F and B by right index finger (normal way)

To speed up the half turns, it is good to turn the slices of the cube in opposite direction by both hands. Instead of moving R2 and R2′ by only right hand, move Lw R’ and Lw’ R respectively.

With this way, you can move each of them by a quarter turn speed.