Hitachi HV-F31CL Operation Manual page 29

Calculate exposure time from value
Shutter Speed[sec] = OFF_VALUE × 0.99
Exp) Value:nnnn = 0078h (for HV-F31CL)
2) In the case that shutter speed is longer than (1 / OFF_VALUE)
Calculate value from exposure time
nnnnh = 10001h - (OFF_VALUE × "Shutter Speed" )
Exp) Exposure time = 1/7.5 sec (for HV-F31CL)
Calculate exposure time from value
Shutter Speed[sec] = ( 10001h – nnnnh ) / OFF_VALUE
(6) AUTO EXPOSURE
Both gain and shutter speed are always adjusted automatically for proper video level.
Adjust the video level manually.
-Manual adjustment-
Setting value 3039xxzz h
The video level decreases toward 80h and increases toward 7Fh.
15
Exposure time = (1/30) × 0.99
10001h- (30×(1/7.5)) = FFFDh
xx: 80h to 7Fh signed (default: 00h)
(nnnn)
(78h)
≒ 1/100(sec)
zz: undefined