Allied International AVT OSCAR V2.4.0 Manuale Utente

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Controlling image capture
 OSCAR Technical Manual V2.4.0
111
Exposure time (shutter) and offset
The exposure (shutter) time for continuous mode and Trigger_Mode_0 is 
based on the following formula:
Shutter register value x time base + offset
The register value is the value set in the corresponding IIDC register 
(SHUTTER [81Ch]). This number is in the range between 1 and 4095.
The shutter register value is multiplied by the time base register value (see 
 on page 184). The default value here 
is set to 20 µs.
A camera-specific offset is also added to this value. It is different for the 
camera models:
Exposure time offset
Example: Oscar F-510C
100 x 20 µs + 74 µs = 2074 µs exposure time
The minimum adjustable exposure time set by register is 20 µs.
 The real minimum exposure time of an Oscar F-510C is then 
20 µs + 74 µs = 94 µs in frame readout mode.
Camera model
Offset interlaced
Offset progressive
Oscar F-320C
46 µs
57 µs
Oscar F-510C
74 µs
83 µs
Oscar F-810C
98 µs
98 µs
 Table 36: Camera-specific offset
Camera
Register value
Timebase
Oscar F-510C in interlaced (frame 
readout) mode
100
20 µs
 Table 37: Register value and time base for Oscar F-510C
Note
L
Generally all Oscar cameras enable certain image settings to 
be modified on the fly, e.g. gain and shutter can be changed 
by the host computer by writing into the gain and shutter 
registers even during camera operation. An uncertainty of 
one or two images remains, as the host is unaware of (espe-
cially with external trigger) when the next image will arrive.