Table 4.

d′ Values for Both Shapes (Discs and Octagons) at Each Eccentricity (15°, 30°, 45°, and 60°).

	Discs d′	Octagons d'
15°	1.35	1.36
30°	0.56	0.61
45°	0.14	0.01
60°	−0.01	0.04
Average	0.46	0.42

Note. The last row (average) shows the mean d′ values for all eccentricities.