IS-1500 User Guide
Thales Visionix, Inc.
MNL- 0024 (D)
Page 55 of 59
distances of 12-15ft with an auto exposure value of 14.2ms. Due to the high exposure value, the sensor should not be moved rapidly
in darker environments as it may cause the captured images to be blurred, decreasing the accuracy of feature detection. The table
below summarizes the performance of the IR InertiaCam. For more information on how to change the camera exposure, refer to the
InertiaCam Exposure Settings section.
Fiducial Type
Fiducial Diameter
(mm)
Distance to Target
(cm)
Camera Exposure
(µs)
Paper
127
1219.2
Auto (14200)
Retroreflective
12
24
Manual (150)
NFT
-
4572
Auto (14200)
7.2
Configuration Settings for IR InertiaCams
7.2.1
Enabling and Disabling the IR Illuminator
A setting in sfHub.info, enabled by default, can be used to enable or disable use of the IR LEDs. Enabling or disabling this setting with
a standard InertiaCam will not have any effect. As shown below, in the InertiaCam section of sfHub.info, set illuminator
1
to enable
the IR illuminator and set illuminator
0
to disable it.
InertiaCam
{
Master
{
ncDataDiv 5
; NavChip data rate divisor (rate = 1000/divisor in Hz)
frameInterval 50000
; Frame interval in microseconds.
manualExposure 2500
; Initial manual exposure
autoExposure 1
; (1) Enable (0) Disable
autoExposureMin 100
; Microseconds.
autoExposureMax 15000
; Microseconds.
autoExpsureLum 1000
; Auto exposure target luminosity
illuminator
1
; IR illuminator enable
}
}
7.2.2
IR Retroreflective Fiducial Recognition
It should be noted that retroreflective fiducials are color-inverted from typical visible light fiducials. With visible light fiducials, the
center eye and patterns are usually white set against a black circle. Retroreflective fiducials use a black center eye and pattern
against a white background. By default, the IS-1500 is configured to read fiducials with white center eyes. In order to use
retroreflective fiducials or visible light fiducials with black center eyes a setting in sfHub.info must be changed. As shown below, in
the ImgProc section of sfHub.info, setting whiteCenterEyes
1
configures the system to read fiducials with white center eyes, while
setting whiteCenterEyes
0
configures the system to read fiducials with black center eyes.
ImgProc
{
Master
{
whiteCenterEyes
0
; (1) white center (0) black center
filterFidMod 100
; Fiducial modulus
imProcDiv 1
; Image processing divisor
undistort 1
; (1) Enable undistortion
}
}