Sigma LBA-500PC Digital Camera User Manual


 
2.6.1.3.5 Camera settings restrictions
Under no circumstances, make any changes to the Advanced. . . Camera settings for the
Pyrocam I.
2.6.1.4 Image synchronization considerations
The Pyrocam I’s CCIR video output is always producing video images at the rate of 25 frames per
second. Furthermore, it only changes output image after acquiring and processing a new image.
Thus the rate of a new output beam image is a function of many variables, including Pulse or
Chop rates, image processing time, and results computational times.
If you are using a Pulsed laser with your Pyrocam I, the Pyrocam will continue to output the
image of the last laser pulse that it receives. As a result, your LBA will continue to collect data
frames that are multiples of the last pulse received by the Pyrocam. To relieve this, you may
want to set up a Trigger input to the LBA. This will cause, at the most, only one image to be
acquired for each Laser Pulse. This can be a tricky situation since the Pyrocam does take a little
time to process each image, and that time will vary somewhat from image to image. Also, if your
laser is triggered faster than the Pyrocam can acquire and update its CCIR display, it will skip
pulses. Thus the LBA can still end up acquiring multiples of some of the processed pulses. You
can also try the solution described below for the Chopped-operating mode.
The exact same type of problem occurs in Chopped mode. The chop frequencies must be either
24Hz or 48Hz. Thus, the CCIR image can never be updating as fast as the chopper is triggering
the Pyrocam. Consequently, the CCIR output is always creating multiple frames of the same
beam profile. In this case, you may want to set the LBA’s Capture interval to a value that will
eliminate or reduce multiple frame captures.
2.6.2 Pyrocam I with Digital LBA-PC’s
LBA-500/7XXPC-D w/ Digital Camera Option
2.6.2.1 Pyrocam I setup requirements:
To use this interface method, your LBA-500/7XXPC must be equipped with the digital camera
option (-D), and your Pyrocam I must be of a later design that has digital output capability. Early
versions of the Pyrocam were not equipped with digital outputs. If your Pyrocam I does not have
a 50 pin connector on its rear cover it can not be interfaced as a digital camera. However, you
can still interface it by using the analog method described in the LBA-300PC interface topic.
Alternately, you can contact Spiricon’s service department and arrange to have your Pyrocam I
upgraded with digital camera output capability.
NOTICE: When interfacing with a Pyrocam I, DO NOT USE THE ULTRACAL! Feature of the LBA-PC. Rather, it
is ESSENTIAL that you periodically re-calibrate the Pyrocam I. Calibrating the Pyrocam I is the only calibration
that should be used with this type of interface.
Operator’s Manual LBA-PC
Doc. No. 10654-001, Rev 4.10
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