#Pyth, 27 bytes
.wsm*50]sm*50]*255%+kd2U8U8 Python equivalent
write_greyscale(sum([50*[sum([50*[255*((k+d)%2)] for k in range(8)])] for d in range(8)])) Try it here (just the colour values)
Output:
#Pyth, 27 bytes
.wsm*50]sm*50]*255%+kd2U8U8 Python equivalent
write_greyscale(sum([50*[sum([50*[255*((k+d)%2)] for k in range(8)])] for d in range(8)])) Try it here (just the colour values)
Output: