Figure 3

Spatially scaling stimuli equates peripheral to foveal Vernier alignment thresholds.

Weber fractions for the fovea and 3 eccentric locations are plotted (data shown in lower contrast) as a function of line length for a representative subject. (a) A scaling factor that minimised the mean squared error between the eccentric and foveal data (see high contrast data points) was calculated. (b) A linear regression line fitted through the data estimates the scaling factor required to increase the size of the eccentric stimuli such that performance is matched to that at the fovea. dw and dn are data reproduced from Whitaker et al., (1992)¹¹.