Comment on "Importance of electron time-of-flight measurements in momentumimaging of saddle-point electron emission" - art. no. 056701

A recent paper by Irby [Phys. Rev. A 60, 1135 (1999)] analyzes the effect o f using calculated, rather than measured, values of the electron time-of-fi ght in soft electron imaging. This paper creates the impression that the an alysis used by Abdallah et al. [Phys. Rev. A 56, 2000 (1997)] might be susp ect and that the saddle-point shifts observed in that paper might be in en or. In fact, the analysis used by Abdallah et nl. is almost exact, as is sh own in this comment, and the conclusions reached in that paper were correct .