If your monitor is functioning properly and calibrated to gamma = 1.8, this pattern will appear smooth neutral gray when viewed from a distance. Any waviness, irregularity, dark areas or color banding indicates incorrect monitor calibration or poor performance. 1.8 is the standard for older Macintosh systems and prepress file interchange. I am not sure how this works on newer MAC monitors.

VIEW "ORIGINAL" SIZE OF IMAGE -- NOT "SMALL"