Is a witness challenged for lack of personal knowledge allowed to testify?

"[A] witness challenged for lack of personal knowledge must . . . be allowed to testify if there is evidence from which a rational trier of fact could find that the witness accurately perceived and recollected the testimonial events." (People v. Anderson (2001) 25 Cal.4th 543, 574, italics omitted.) A determination of a witness's ability to perceive and recall is left to the discretion of the trial judge and that "determination will be upheld in the absence of a clear abuse of discretion. [Citations.]" (Id. at p. 573.)