Winston Lutz couch shift conventions

Google Groups
1

Hi,
I’m using a Winston Lutz module with a Truebeam and the up/down instructions seem reversed:

print(wl.bb_shift_instructions(couch_vrt=3.5, couch_lng=34.92, couch_lat=-0.01))
: When I follow the suggested couch positions, I only get farther from the field center.
Is it possible to modify the directions?

Thanks,
Eli

2

The couch position should be passed in centimeters. That’s probably an inconsistency as everything else is in mm. When I create mock images of a BB 2mm high the instructions seem correct:

print(wl.bb_shift_instructions(couch_vrt=3.5, couch_lng=0, couch_lat=0))

LEFT 0.00mm; IN 0.00mm; DOWN 2.01mm
New couch coordinates (mm): VRT: 3.30; LNG: 0.00; LAT: -0.00

WL 2mm high.zip (189 KB)