They are not colors they are shades
        
                    
             
        
        
        
Without the clay sculpture, it would be impossible to make the mold to cast the bronze
        
             
        
        
        
Answer:
1. Photography isn't made by hand (with pencils, paint brushes, or sculpting tools)
2. You can edit your pictures through different apps and add filters
3. Photography can be quicker then drawing and sculptor in that photography you can walk by a beautiful flower and take a picture and edit it later but with drawing you would sit there and draw what you see. 
Hopefully this helps!