1. A nuclear medicine tomographic imaging apparatus, comprising: a detector capable of orbiting about a patient to acquire projection data at a plurality of view angles; a control unit that varies the amount of time that said detector remains at a particular view angle in response to a control signal; and a processing unit that develops said control signal in response to a desired measure of image quality wherein to develop said control signal said processing unit is adapted to perform a pre-scan of said patient for a plurality of view angles over a period of time shorter than a time required for a clinical scan, and obtain pre-scan data; subsample said pre-scan data with a varied dwell time to obtain simulated varied dwell time data; compare a reconstructed image of said pre-scan data with a reconstructed image of said simulated varied dwell time data; determine whether the result of said comparison falls within a predefined acceptable range; modify said varied dwell time to obtain a modified set of simulated varied dwell time data if the result of said comparison is outside of said predefined acceptable range; and use said varied dwell time in a clinical scan of said patient if the result of said comparison is within said predefined acceptable range.