Table 1.

The sequence of images required to determinate radiation isocentre.

	Collimator position [⁰]	Gantry position [⁰]	Couch position [⁰]
Image 1	0	0	0
Image 2	90	0	0
Image 3	0	0	0
Image 4	270	0	0
Image 5	0	0	0
Image 6	0	90	0
Image 7	0	180	0
Image 8	0	270	0
Image 9	0	0	90
Image 10	0	0	0
Image 11	0	0	270