How to have colourful contours superimposed on a grayscale (imshow) background?

Hi! I need to create contours (with the ordinary colorbar) superimposed on a grayscale image, which I have plotted using imshow. The contours tend to appear in white. Is there any way to give them colours?

Here is my code:

Brain=load('Raw.mat');

background=mat2gray(Brain(:,:,26));

figure

imshow(background)

hold on

densities=[1,2,4,8,16,32,64,128,256,512,1024,2048,4096,8000];

contour(volume(:,:,26),densities)

hold off

Answer 1

[Chad Greene]

Here's one way. If you turn the background matrix into RGB values, imshow won't try to attach the background image to the current colormap.

bg = ind2rgb(imread('cameraman.tif'),gray(256)); 
imshow(bg)
hold on
contour(peaks(256))

Answer 2

[Zohreh Khazraei Manesh]

Thank you for your super fast response Chad!

The solution is smart and works perfectly!

[Chad Greene]

I'm glad it works for ya!