9
Basic Functions
AE – Bright
The bright control function adjusts both the gain and
iris using an internal algorithm according to a
brightness level freely set by the user. Exposure is
controlled by gain when dark and by iris when bright.
As both gain and iris are fixed, this mode is used when
exposing at a fixed camera sensitivity. When switching
from Full Auto or Shutter Priority Mode to Bright
Mode, the current status will be retained for a short
period of time.
Only when the AE mode is set to “Full Auto” or
“Shutter Priority,” the user can switch it to “Bright.”
Data
Iris
Gain
Data
Iris
Gain
1F
F1.4
28 dB
0F
F2.0
0 dB
1E
F1.4
26 dB
0E
F2.4
0 dB
1D
F1.4
24 dB
0D
F2.8
0 dB
1C
F1.4
22 dB
0C
F3.4
0 dB
1B
F1.4
20 dB
0B
F4.0
0 dB
1A
F1.4
18 dB
0A
F4.8
0 dB
19
F1.4
16 dB
09
F5.6
0 dB
18
F1.4
14 dB
08
F6.8
0 dB
17
F1.4
12 dB
07
F8.0
0 dB
16
F1.4
10 dB
06
F9.6
0 dB
15
F1.4
8 dB
05
F11
0 dB
14
F1.4
6 dB
04
F14
0 dB
13
F1.4
4 dB
03
F16
0 dB
12
F1.4
2 dB
02
F19
0 dB
11
F1.4
0 dB
01
F22
0 dB
10
F1.6
0 dB
00
CLOSE
0 dB
Spot Exposure Mode
In Full Auto AE, the level for the entire screen is
computed and the optimum Auto Iris and Gain levels
are determined. In Spot AE, a particular section of the
subject can be designated, and then that portion of the
image can be weighted and a value computed so that
Iris and Gain can be optimized to obtain an image.
For example, in an image with a lot of movement and
with varying levels of brightness, portions without
much change can be designated as such a “spot,” and
changes to the screen can be minimized in that area.
As shown in the diagram below, a range of 16 blocks
vertically and 16 blocks horizontally can be
designated.
In the case where the center is designated (shown in
black), the level is computed along with a weighted
value for the surrounding block (shaded), including the
specified portions; and then the Gain and Iris are set.
The value of the designated portions and the
surrounding areas should be calculated as 90% and the
rest should be set to 10%. The range of the Spot AE
frame is fixed to five blocks vertically and four blocks
horizontally.
(8,8)
Horizontal 16
Vertical 16
0
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
1
2
3
4
5
6
7
8
9 A B C D E F
MIN
MAX
AGC
CLOSE
OPEN
IRIS
Gain
Dark
Bright
IRIS curve
Gain curve
Controlled
by gain
Controlled by IRIS
Bright limit which controllable
for this unit
When switching from the Shutter Priority mode to the
Bright mode, the shutter speed set in the Shutter
Priority mode is maintained.