Hitachi HV-D30 operation manual 38



Long-Time Store Mode

In case that illumination on the subject is insufficient, just increasing the gain of the camera may cause an increase in noise, resulting in an unclear image. In such a situation, it is advisable to select the long-time store mode using the external memory. Thereby, the image can be brighter and clearer according to the stored amount of image. This camera is provided with two kinds of image store functions (CCD MODE:FLD/FRM in SUB MENU 1). When one of these image store functions is used, video signal output is delivered from the camera with the timing shown below.

Since the degree of after-image increases for a moving subject because of image storing, it is recommended to use the image store function when taking a still picture or scene.

	Field store mode
Even field	CCD line A
odd field	CCD line B
Even field	CCD line A
	CCD line B

Store time: 1/15 s (Example)

In the field store mode, both the CCD lines A and B are read out simultaneously. After completion of storing, video signal output is made on the next field. Immediately before the field on which video signal output is made, the WE signal is delivered from the D-SUB connector equipped on the rear panel.

VD signal

Store charge on CCD line A Store charge on CCD line B

Video signal

#C		#D		#E		#F
$C		$D		$E		$F
	#C		#D		#E
	$C		$D		$E

WE signal

Frame store mode

Even field	CCD line A
Odd field	CCD line B
Even field	CCD line A
	CCD line B
Odd field

In the frame store mode, each of the CCD lines A and B is read out individually. Therefore, the vertical resolution is superior. After completion storing, video signal output is made between two fields. Immediately before the field on which video signal output is made, the WE signal is delivered from the D-SUB connector equipped on the rear panel.

Store time: 1/15 s (Example)

VD signal

Store charge on CCD line A

Store charge on CCD line B

#C	#D	#E	#F
$C	$D	$E	$F

Video signal

#C

$C

#D

$D

#E

$E

WE signal

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