Panasonic PV-500, Руководство пользователя

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1.
Select the camera No. to set in “Camera” window.
2.
Select “Gain”.
Gain value is displayed.
- Gain Range: 0.25 to 1.00 (Initial Value: 0.50)
- Setting unit: 0.01
For details, refer to page 65 Setting Camera Gain”.
3.
Set gain value.
Setting the display image to “Live” updates it to the image captured with the specified gain value. To
observe the image easily, set “Window Transparency (SETUP menu)” to a larger value.
4.
Select "Offset".
It can be set for gray cameras.
- - Offset Range: 0 to 1000 (Initial Value: 0)
For details, refer to page 67 “Setting Offset”.
Setting Camera Gain
What is Camera Gain?
Camera gain is sensitivity of a camera. As increasing the value, an image turns to be lighter. Also, by using
this function, the part that is difficult to be distinguished because of a small difference in gray values can be
changed to the image with high contrast. On the other hand, it will be sensitive to the variation of the
brightness surrounding the work if the gain value is increased, and the image will be rougher due to
increased noises.
Adjust camera gain when you cannot obtain a desired image even though you have adjusted lens aperture
and lighting illuminance.
The range of gray values used
for inspections is determined by
the setting of camera gain
values.
* As shown in the above figure, the ranges where the squires are located are different between the cases
that "the upper and lower 5% of camera gray values are not used" and "only 90% of darker data is used",
however, the both percentages of the usage of camera gray values are 90%. In the both cases, the gain to
be set is 90%. [Offset] is provided among the items to determine the positions of squares. For details, refer
to "Offset".
Image data (10-bit) loaded in a camera has a value in the range of 0 to 1023. This value is a camera gray
value. As PV500 performs image processing with 8-bit gray images in the range of 0 to 255, inspection
images are converted to data in the range of 0 to 255. Camera gain is a value which indicates the
conversion rate of camera gray value.