Others; About Alc And Eei Operations - JVC KY-F70B Instructions Manual

8. Others

About ALC and EEI operations

ALC stands for Automatic Level Control and EEI for Extended Electronic Iris. (
By making the respective settings, the Automatic Level Control (ALC) will operate under dark
lighting, and the electronic shutter (EEI) will operate under bright lighting. Furthermore, setting
the IRIS mode to AUTO will synchronize sensitivity, iris and electronic shutter so that an appro-
priate signal level can be acquired automatically at all times.
The ALC mode increases sensitivity from 0dB (ISO100) to +12dB (ISO400) under dark lighting
and the EEI mode automatically adjusts the electronic shutter within the range of 1/7.5 s to
1/2384.7 s (calculated value) when in FINE under bright lighting (1/30.2 s to 1/2384.7 s for DRAFT).
In other words, the signal level is adjusted in the range of 2 graduations of the aperture under
dark lighting and 8 graduations when in FINE under bright lighting (6 graduations in DRAFT).
When the IRIS mode is set to manual, the sensitivity and electronic shutter change continuously
whilst the iris setting stays fixed. (
This feature holds the advantage of being able to record under changing light conditions without
the depth of field altering.
MEMO
• The status of ALC and EEI can be displayed on the screen. (
• When EEI is used, the amount of change in one step of the signal level will be large and the precision
becomes bad as the shutter speed is faster.
Operational range
Light: lx
4 8
FINE
E70
16 31 63 125
ISO100
ALC
ISO400 ISO200
F2.8
ALC
DRAFT
ISO400 ISO200
page 50 IRIS MODE)
250 500 1000 2000 4000 8000 16000
F4 F5.6 F8 F11
ISO100
F2.8 F4 F5.6
page 57 ON SCREEN)
32000
1/7.5
EEI
1/15 1/30 1/60
F16
1/30.2
1/60
F8 F11 F12
page 51, 52)
64000
640000
1/120 1/2384.7
EEI
1/120 1/2384.7