Rendering an essentially continuous IG image onto the discrete-pixel array of most display devices, as well as graphical processing such as antialias filtering, can result in significant variations in displayed target size and hence simulated distance. Using videotape recordings obtained from a CRT-based, flight-simulator display, we have directly measured changes in size, over a three-second simulation interval, of target aircraft simulated at distances between 3000 and 11000 feet. In Experiment 1, the percentile of the measured target-size distribution which corresponded to the nominal target size was found to change with simulated distance. Additionally, an interaction was found between pixel count (1280x1024 and 2048x1536) and antialias filtering (0 and 2x). In Experiment 2, a single intermediate pixel count (1600x1200) was tested, and in addition, eight target gray-levels were tested perceptually, in order to directly compare the videotaped imagery with what was visible on the screen. It was found that the percentile corresponding to nominal target size varied with both simulated distance and antialiasing condition (0 and 4x). In both experiments, for the larger (i.e., closer) targets, the nominal target size corresponded to about the 96^th percentile of the distribution of measured sizes. As target size was decreased, nominal size was found to correspond to as low as the 60th percentile. Further, in both experiments, the functions relating the relevant size-distribution percentiles to simulated distance were nonlinear, and in Experiment 2 they were different for each of the antialiasing conditions tested. The data indicate that the average size of targets displayed in CRT-based flight simulators is smaller than would be expected from their nominal distance as defined by the IG. In addition, the unexpected complexities found in the size-distribution data indicate that accurately adjusting displayed target size to reflect a chosen target distance will require corrections that are dependent on simulated distance.