Campbell Scientific CC640 Digital Camera - Manual (Page 26)

CC640 Digital Camera
6.2 External Trigger Mode
An image acquisition can also be triggered from the Ext. Input Signal on the
camera. It is recommended that a short pulse be used to initiate the image
acquisition. If a positive voltage is applied and not removed before the image
acquisition sequence is complete, the camera will begin another image
acquisition immediately after. An image acquisition can be as short as 10
Seconds. See Section 2.3 for a program example.
External Trigger Mode can be used in conjunction with the Self-
Timed Mode by following all the steps as listed in this section. NOTE
7. Image Quality
7.1 Lighting Conditions
Lighting conditions have the greatest influence on image quality. The CC640
camera produces the best images under normal daylight conditions. Pictures
taken in good daylight conditions produce crisper and brighter images.
The CC640 uses the entire image to adjust the exposure settings for a particular
scene. Scenes that contain small variations in light intensities will produce
better images also. In scenes with high variations in light intensities, such as a
bright sky and a dark horizon, the image may contain portions that are under-
exposed and portions that are over-exposed. The CC640 utilizes various
techniques to produce an overall good picture under most lighting conditions.
When the CC640 is over-exposed by an overly bright object, such as the sun in
a sky shot, the over-exposed object may begin to turn black. This is a result of
the CMOS image sensor being over-exposed to light and becoming saturated.
It is normal operation for the center of the Sun to appear black under certain
lighting conditions.
7.2 Night Time Images
The camera does not produce distinguishable images at night time. If lighting
is present (such as street lights), then objects may become noticeable.
7.3 Date and Time Stamp
Setting the Time Stamp option of the camera to ON will add a banner to the
bottom of the images (Figure 10). The banner adds 24 pixel rows to the image
and increases the size of the image from 640x480 to 640x504 pixels.
The banner includes the text entered for the fixed file name. The text that can
be displayed includes numbers 0-9, letters A-Z (converted to upper case), and
an underscore symbol. Unsupported symbols/characters are displayed as a
space.
Following the fixed file name string is the Date and time stamp. The First 3
characters are used for the month followed by the day of month and year. The
time is HH:MM in 24 hour clock format.
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