CV-M77
Set SW1-5 and SW1-6 on the rear plate of the camera to “ON” and SW1-7 to OFF or use the RS 232C control to set-up the PWC mode of the camera.
6.3.3Frame-delay Readout Mode
This trigger mode operates in H non-reset mode. In H non-reset mode the trigger and HD is synchronized. The exposure will start at the first HD pulse after the falling edge of the external trigger signal. The exposure ends at the rising edge of the external trigger signal. The trigger pulse must be longer than >1H. To avoid jitter, the camera should be synchronized to an external HD. There are some requirements to the phase between the ext. HD and the Ext. trigger. The falling and rising edge off the trigger should be within 8 ∝sec. before the falling and rising edge of the ext. HD pulse and not later than 2∝sec after the falling and rising edge of the HD pulse (see fig. 6.3) The resulting video signal will first start to be read out after the input of an external VD signal. The readout delay should not be to long due to visible dark current noise generated in the CCD sensor. The WEN pulse indicates the start of valid video signal. Refer to timing charts for details.
A new trigger pulse must not be applied before the video read out has finished.
To use this mode:
Set SW1-5 to SW1-7 on the rear plate of the camera to “ON” or use the RS 232C control to set-up the Frame-delay Readout Mode of the camera.
6.3.4Long Time Exposure Mode
The exposure time is the interval between 2 ext. VD pulses sent to the VD input of the camera. The exposure starts after input of the first ext. VD pulse, and ends after the next input of the ext. VD pulse, which again starts a new exposure.
The long time exposure is a continuous process where each external VD pulse will synchronize the camera, stop on exposure, start a new exposure and read out the previous accumulated signal. The exposure can be selected in intervals of complete vertical timing periods (=792H)
This long time exposure mode operates in H non-reset mode. In H non-reset mode the external VD signal and the internal HD signal are synchronized. The exposure will start at the first HD pulse after the falling edge of the external trigger signal. Se figure 6-2 for the phase relationship between ext. HD and ext. VD pulses.
To use this mode:
Set SW1-1 to SW1-7 on the rear plate of the camera to OFF or use the RS 232C control. Apply the continuous external VD signal.
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