Triggering FLIR SC325 Camera

[AkshayHari]

Hello,

I am trying to trigger a FLIR SC325 camera using an external hardward trigger into one of the camera's digital inputs (I have a TTL pulse generator that I am sending into one of the digital inputs). I looked at the camera's settings using MAX, and found one group of settings called "CameraIO". I set one of the digital inputs to have rising edge sensitivity and a configuration of "EnableImageFlow". However, when I run the LabVIEW example Grab.vi, the camera immediately starts recording even when no signal is connected to the digital input.

Any thoughts?

Thank you.

[Prickly_Pear]

This problem can be a little tricky because every camera has different attributes that are defined by the camera manufacturer. When the GigE camera is plugged in, it loads an XML file onto the computer that MAX used to generate a list of available camera controls. Because of that, it is possible that the attribute has an obscure name. Look for anything that talks about a trigger. This document mentions a "Trigger Mode" attribute under the Camera Attributes tab: http://digital.ni.com/public.nsf/allkb/17A956942535A2C786257419007778FF?OpenDocument

Also, it could be that FLIR has a configuration utility that can communicate directly with the camera. It is possible that the trigger needs to be enabled using this utility.

Jeremy P.

[MoviJOHN]

Hardware triggering is not reliable on these cameras.  I believe there is an application note on support.flir.com on the subject.

[AkshayHari]

In what way is hardware triggering not reliable?

I have done hardware triggering when working directly with FLIR's software with no issues. I would like to build a more extensive application now, and that's why I'm trying to move to LabVIEW. Have you had difficulties with hardware triggering?

Thanks.

[MoviJOHN]

Image delivery is not guaranteed. Sometimes you will get the same image two or more times. I do not recall the specifics.

[MoviJOHN]

At the very least , you should compare images to avoid this, or detect when it happens.

[AkshayHari]

Thanks a lot for everyone's input.

Is there a particular block I should use in order to store the actual temperature values from the images that are captured? Capturing the images without any triggering is straightforward enough, but how do I convert these images to temperatures within the LabVIEW program? Is there a certain block that accesses the "metadata" of the image?

Also, I still have not had any luck with the triggering. If someone out there has successfully triggered a FLIR camera using LabVIEW (and without using the FLIR ThermoVision toolkit), please let me know!

Thank you very much.

[MoviJOHN]

The camera should have a selector with RADIOMETRIC, 10mK, 100mK, or something like that.  Radiometric cannot be used to convert to temperature, except by FLIR propietery software, so you are left with the 10mK and 100mK modes.

It works like this:

First, you need to cast the image into a SGL.

10mK - The value increment is equal to 10mK, so dividing the raw value of a pixel (or the entire image) by 100 will give you the temperature in °K. Subtract 273.15 to convert to °C.

This only works for raw values >=0 and <= 32767, which represent the cooler temperatures of the camera's temperature range.

For anything hotter than 32767, the camera reports those values starting at -32768 all the way up to -1 (the hotest temperature).  So, if you are dealing with high temperatures, you need to cast the image as SGL, and then you need to add 65536 to every negative value in the image.  You can best do this by creating a mask consisting of negative pixels being represented by 65536, and positive pixels (and zero) being represented by Zero.  You can the cast the mask as SGL and add it to the original image.