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Long time integration, Cv-m91 – JAI CV-M91 User Manual

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CV-M91

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6.2.5. Long time integration
The exposure time is the interval between 2 ext. VD pulses sent to the VD input. (Pin No. 7 of
the 12-pin connector). The exposure starts after input of the first ext. VD pulse, and ends after

the next input of the next ext. VD pulse, which again starts a new exposure. The long time
exposure is a continuous process where each external VD will synchronize the camera, stop the
exposure, start a new exposure and read out the previous accumulated signal. The exposure
time can be selected in intervals of complete vertical timing periods. (Interlaced frame: EIA
525H and CCIR 625H. Non-interlaced field EIA 262H and CCIR 312H).
Refer to “7. Configuring the Camera.”

To use this mode:

Set function:

Trigger mode to “Long Time integrationl”. SW 1-4 to OFF

On PK8407: JP301 open, JP302 short, JP311 short.

Accumulation to “Field” or “Frame”. SW 301-4 to OFF or ON

Scanning to “Non-interlaced” or “Interlaced”. SW 1-5 to ON or OFF

Shutter Speed to “OFF ”. SW 1-1 through 1-3 to OFF

Other

functions

Input:

Ext. VD to pin 7 on 12-pin connector

(Ext. HD to pin 7 on 12-pin connector). Option

Important notes on using this mode.

• The exposure range is from 1 field to ∞. However it is recommended not to use exposure

over 2 seconds due visible dark current signals.

• The ext. VD signal should follow the camera sync system and interlace setting.
• Requirements to HD/VD phase is shown in fig. 10.


Fig. 27. Long time interlaced field integration


Fig. 28. Long time interlaced frame integration


Fig. 29. Long time non-interlaced field integration