I am having a problem with comparing two different blots on two different pictures. One blot on one picture is light while the other blot on the other picture is much darker. However, the lighter blot is still giving me a stronger intensity value than the darker blot, which doesn't make any sense. The signal intensity values that I am getting don't correspond to what I am seeing on my gels. Another problem is that my gels don't have a sample control but should not Image J be able to correctly assign the darker blot a much higher intensity value than the lighter anyways? Is it a background issue? Any help would be immensely appreciated!