I'm trying to convert a 2D array to grayscale but using mat2gray doesn't do anything and imshow() appears to create a binary image that when I graph I cannot rotate it, e.g. the original array is 2d but maps in 3d. So, what is the best way to take a grayscale of 2d array in Matlab so if you have A=rand(5,10) or something and want to take a grayscale of that, what is the best way?