Center the test tool properly with respect to the imaging assembly.
Use the image chain to decrease the amount of radiation received while
moving the test tool and to prevent damage to the components.
h. Tape the test tool to the table top to minimize the possibility of any movement.
Perform the beam restriction test in the fluoroscopic mode.
Start the fluoroscopic exposure.
Observe the test tool image.
(3) Carefully insert the brass slides into the test tool channels with the ends
of the slides just visible at the edges of the viewed image on the fluoroscope or mirror
The ends of the slides define the visual field of the image intensifier system.
(4) Discontinue the fluoroscopic exposure.
(5) Place an 8- x 10-inch cardboard with ready pack film on top of the test
(6) Again, start the fluoroscopy and set the controls for automatic brightness
If this is not possible, set the fluoroscopic technique factor to low values
(which may be increased later, if necessary) to prevent damage to the
components in the image chain.
Adjust the technique and time so that the proper film density will result.
If using a screenless cassette, place a one-eighth inch sheet of lead over the
cassette to prevent exposure to the image intensifier.
By using maximum mA and higher kVp you will decrease the needed
(8) Test for all field size modes, for the small and the large focal spot in both
manual and automatic modes.
(9) Examine the fluoroscopic image and ensure that each of the collimator
edges (assuming a rectangular collimator system is present) is visible just within the
edges of the visual field as seen on the fluoroscopic television or the mirror optics.
(10) Process the test film.