What is the test for determining the appropriate amount of time spent by an attorney in presenting a lawsuit?

"Serrano III requires the trial court to first determine a 'touchstone' or 'lodestar' figure based on a 'careful compilation of the time spent and reasonable hourly compensation for each attorney ... involved in the presentation of the case.' [Citations.] That figure may then be increased or reduced by the application of a 'multiplier' after the trial court has considered other factors concerning the lawsuit. [Fn. omitted.]" (Press v. Lucky Stores, Inc., supra, 34 Cal.3d 311, 322, 193 Cal.Rptr. 900, 667 P.2d 704.)