imagesc automatically scales your image to 'fit' to the colorbar. It can be a huge pain sometimes. If you can get away with it, just plot the images in the same picture like,
they'd have to be the same size though...
another thing you could do is reset the range in the colorbar so that it matches the first image.
create a colormap and crop off some stuff,
cm = jet(100);cm(end-39:end,:)=;colormap(cm)
or, you could just use image() to plot the pics... if they're too dark, just multiply them by some value so they show up nicely. good luck