Measurement methods
12
Example
LED-Panel settings:
Operating mode TRIGGER EXT
Exposure time (1/x s) 1/10 s
LED No. 2 is lit up (Figure 2):
Shutter lag is 0.2 seconds (2 * 1/10 s)
4.2 Shutter lag with autofocus time
The LED-Panel is used in TRIGGER EXT operating mode and a micro switch is connected. Two
pictures are taken and the shutter lag is calculated.
•
As described in Shutter lag without autofocus time. The shutter lag without autofocus
time is calculated.
•
The camera focus is set to infinity. Afterwards a picture of the LED-Panel is taken with
the aid of the micro switch. After the time for the auto focus and shutter lag has passed,
the camera takes a picture of the running LED-Panel. The time passed since the micro
switch (and the release button) was pressed and autofocus was completed can be read
with the aid of the lit LEDs in this picture.
The autofocus time can be calculated as the difference between shutter lag with autofocus time
(Figure 4) and shutter lag without autofocus time (Figure 3).
Autofocus time = (shutter lag with autofocus time)
– (shutter lag without autofocus time)
Figure 3
Shutter lag without autofocus time
Figure 4
Shutter lag with autofocus time
