As I understand it, there are several definitions of Campimetry.  I
had tried one at:

http://myvisiontest.com/afterimage.html

.. which is of the snow field type.  In running this test, I could
make the blue dot disappear (by changing the eye fixation point and
distance to the screen), and also by moving black arrow (making the
arrow disappear), but the noise field underneath remained the same
(????).  So the "normal blind spot" would not show up as some kind of
different visual effect.  Some time ago, I remember my normal blind
spot filling in the area of a multi-colored plaid cloth.  Felt like
the same effect.

Don W.