# X-Ray versus Light Field dimensions difference

In the example figures above, the witdh is vertical because the test object is rotated by 90°

From the dimensions of the two fields (X-Ray and Light) the two differences of width and height are calculated. The difference has a sign: negative values mean that the X-Ray field is smaller than the light field.

Fields width difference = :WXWL$W_X - W_L$

Fields height difference = :HXHL$H_X - H_L$

where:

WX = Width of the X-Ray field
WL = Width of the light field
HX = Height of the X-Ray field
HL = Height of the light field