You should see that a selection is made. Now the image looks lighter but we'll fix it. This is usefull since we what to get rid of all the white area so it can be replace by colors. Grey areas are partially selected. All greys are now replace by transparent black.
All white area are transparent and grey areas are partially transparent.
We had to go over it again with black to turn all the grays to varying degrees of transparent black. You'll see the effectiveness of this when we start to paint underneath. When your more experience, you'll find this step can be done in about 10-20 seconds. The reason I like this method over simpler one is that there's a minor advantage. I'll let you know what it is near the end.