Sony HKSR-9003, Руководство по эксплуатации

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Selecting the Gamma 68
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Note that ITU-R709 provides 4.5-times gain near
black. Select the No. 6 (×5.0) curve when you
need higher contrast near black.
Hyper Gamma enables the wide dynamic range of the CCD sensors to be reproduced with smooth contrast
without using the Knee function.
This camera provides the following eight hyper gamma choices:
Available Hyper Gamma choices
1) Naming rule: HG + 3 digits of dynamic range value +
1’s digit of white limit + G + video output value with
18% gray card
For the respective curves, see the figures in
“HyperGamma curves” (page 69).
Reproducibility of high luminance areas
You can select the dynamic range from among
325%, 460%, and 800%. Selecting a wide
dynamic range, such as 800%, enables
reproduction of gradation at high luminance.
However, the brightness of intermediate
gradation will be lowered.
White limit
You can select either 109% or 100% for the
maximum value of video output (white limit).
While reproduction up to 109% is possible with
SDI outputs, only 100% may be available,
depending on the environment of the production
system. In such conditions, select 100% as the
white limit.
Midtone
You can select two values for the brightness of
intermediate gradation areas around skin tones.
Selecting a curve for bright intermediate
gradation may slightly inhibit reproducibility of
the high luminance.
To select HyperGamma
1
Select HYPER GAMMA on the first
line of TABLE on the <GAMMA> page
and select the hyper gamma curve most
suitable to the shooting conditions and
purpose.
2
Observing the output video level for a
gray card of 18% reflection rate on a
waveform monitor, adjust the iris so
that the level becomes equal to that
shown in the “Video output with 18%
gray card” column of the “Available
Hyper Gamma choices” table. (The iris
setting in this condition is the standard
iris setting for the selected hyper
gamma.)
Using HyperGamma
No.
Name
1) Dynamic range White limit Video output with 18% gray card
(video input 20%)
1 HG3250G36 325% 100% 36%
2 HG4600G30 460% 100% 30%
3 HG3259G40 325% 109% 40%
4 HG4609G33 460% 109% 33%
5 HG8000G36 800% 100% 36%
6 HG8000G30 800% 100% 30%
7 HG8009G40 800% 109% 40%
8 HG8009G33 800% 109% 33%