Table 5.

Elekta Precise 60° wedge factors (WF) for 6‐MV and 10‐MV photons. Air and water wedge factors were measured with a 0.6 cm³ Farmer chamber. The difference (%) between ${\text{WF}}_{\text{air},155\text{cm}}$ and ${\text{WF}}_{\text{EPID}}$ is reported in the last column.

Field size	Energy	In water	In air	In air	iViewGT	% Diff
$({\text{cm}}^2)$	(MV)	100 cm	100 cm	155 cm	EPID
		$\text{SSD}+d_{max}$	SCD	SCD
$5\times 5$	6	0.286	0.288	0.287	0.248	15.7%
$10\times 10$	6	0.293	0.295	0.293	0.251	16.7%
$20\times 20$	6	0.306	0.307	0.304	0.260	16.9%
$5\times 5$	10	0.308	0.303	0.301	0.280	7.5%
$10\times 10$	10	0.311	0.310	0.308	0.282	9.2%
$20\times 20$	10	0.328	0.323	0.319	0.293	8.9%