Photron Fastcam SA2, Hardware Manual

Page: 39 / 101

27 FASTCAM SA2 / SA2 RV Hardware Manual
3.4. Selecting the Shutter Speed
The shutter speed is independent of the frame rate, and you can control the exposure time in one
frame using the electric shutter. By making an exposure that is of a shorter period than the frame rate,
high-speed objects can be photographed blur-free.
The shutter speed can be set from 1/frame s to a maximum of 1/3670,000 s (approximately 2.76us).

The numerical value of [0.xxx S] display serves as actual exposure time.

The numerical value of [1/xxx S] display is round figure. It differs from actual exposure time a little.

For more information of Shutter Speed, refer to “5.1.6. Shutter Speed List”, page 74.
3.4.1. Changing SHUTTER MODE
By switching between [MODE1] and [MODE2] on the [SHUTTER MODE] submenu on the
[SHUTTER] menu, the shutter speed value first used when the frame rate is changed can be set.
MODE1
: Changing the frame rate automatically sets the shutter speed to 1/frame s.
MODE2 : Changing the frame rate does not change the shutter speed, it maintains the current
setting.
3.4.2. Setting Dual Slope Shutter function
DS SHUTTER is a mode that records the high brightness portion and low brightness portion in one
image at the same time by adjusting the light exposure internally in the sensor. By using this function,
when recording a subject with an extremely large difference in the brightness in the image, the
sensor functions so that it can record at the proper light exposure for both the high brightness and
low brightness portions.

This function cannot be used with the operations below.
■ When the AUTO EXPOSURE function is used
■ When the trigger mode is RANDOM RESET

When using the DS SHUTTER function on a color model, there are situations where the colors
become unbalanced and the color reproducibility degrades.
The light exposure adjustment can be set from 0% to 95% in 5% increments according to the subject
to be recorded.

The amount of adjustment is expressed as %.For the strength of the adjustment, 0% is no
adjustment, 95% is the maximum effect.