Analyses of within-object fixation position distributions considered three object size categories (small, medium, large) and two horizontal launch site categories (near vs. far). An initial set of analyses demonstrated that the PVL varied with object size (
Figure 1). For both medium-sized and large objects, the data showed a PVL such that viewers preferred to send their eyes to the center of objects. This preference for object centers over object ends was stronger for large objects than for medium-sized objects. For small objects, however, there was no evidence for a PVL, suggesting that they were not targeted or fixated optimally. A second set of analyses demonstrated additional effects of launch site distance, which interacted with object size effects in a very specific and interesting manner. Analyses considered saccades that entered objects along the horizontal axis, that is, from the left or from the right (the data were collapsed across the two horizontal categories). For far launch sites (>5°), there was no PVL for medium-sized objects (
Figure 2b), suggesting that those objects were too small to perceive their boundaries without the high acuity present in central vision. For near launch sites (<5°), however, there was a horizontal PVL for medium-sized objects (
Figure 2a), suggesting that object boundaries could be identified in parafoveal vision. A different pattern of results was observed for large objects, which were further divided into two subcategories (“smaller large” vs. “larger large” objects). First, a PVL was also observed for far launch sites (>5.7°), suggesting that those objects were sufficiently large to target them optimally in peripheral vision. Moreover, launch site distance and object width affected the mean of landing position distributions in an additive manner (
Figure 3). For far launch sites, the distribution of landing positions was shifted to the left, toward the edge closest to the launch site. A similar leftward shift was observed for “larger large” as compared with “smaller large” objects. Numerically, the launch site effect was greater for the largest objects. When the eyes were relatively close to the target object (near launch sites), we observed an overshoot such that the PVL was situated somewhat beyond object center (
Figure 3c). In contrast, when the eyes were farther away (far launch sites), we observed a tendency to undershoot object center (
Figure 3d). In addition, the data tentatively suggest that hypometric saccades, in which the eyes undershoot the target, are less common in complex-scene viewing than in reading (McConkie et al.,
1988; Rayner,
1979) or simple oculomotor aiming tasks (e.g., Henson,
1979).