Ok, a few days ago our lead programmer and I tried calibrating our camera for green. We placed it under a 1000 watt mercury vapor lamp (our teacher had one lying around…don’t ask). We followed the instructions for calibration which were to grab a frame and click on green and let it calibrate and we would get an exposure value. We received a value of 15, which our programmer placed into the code where the exposure values should be placed. After that we loaded the code onto the OI and we were tracking green succesfully. Today I tried to calibrate for yellow. Nothing was working. It could not find it for any reason. We did get one exposure value of 57 at one point, but could not get it again. After searching around on the forums I found out that you can select the color and highlight it in the picture and you will get corresponding RGB values. But this is not the exposure value, so where in the code would these values be placed. Also I found out that Dave Lavery said that each event will give us the calibration numbers for each location at the event. Now what numbers do they give us? The exposure values or the RGB values? If anyone can tell me a surefire way to calibrate the camera properly and where to place the values that we receive into the code, please tell me. Any help would be appreciated.
They should give us exposure values at the events.
Hm…our team had the same problem over the weekend. We tried for two days to calibrate the camera! With different types of lighting and different target locations. But no luck. With just the floorescent lighting we could get yellow, but none of the other colors. Then with the halogen work light we could get red but none of the other colors. And we could never get green. Arghh… This doesn’t help us since don’t you need all the colors calibrated under the same light conditions that you will run your robot in? Well anyways, back to the question. I noticed that you said you only calibrated green and were able to track green. Is this really true? Do you not need to calibrate all the colors if you just want to track one color? Also, were you tracking the color using the demo mode of the camera or the default camera code given on IFI robotics?
Thanks!
Ya we were tracking our green vision tetra with no problems that we could see except the camera was moving jerkily. All we did was enter the exposure value that we received from the GUI into the camera code and then loaded the camera code onto the OI. Once it was loaded and a joystick was attached to Port 2 (this is a requirement since the trigger needs to be pushed in this port to activate tracking). Once we hit the trigger button it started finding the green on the vision tetra. So I guess you do not need the other color exposure values. And I guess it was the default camera code as well. Currently as I type I am recharging my backup battery (how it dropped voltage I do not know) so I can receive an exposure value for green under our fluorescent lighting.
Just curious, the color of the vision tetra seen on the kick off video, and the color of the vision tetra as seen on the camera calibration manual (camera snapshot) seem to look much darker than the fluorescent green paint that we have. What does your paint look like? Is it a darker green? Or fluorescent green? Did anyone attend the kick off and see the tetra? Was it actually fluorescent green?
The paint we bought were according to the specs provided by FIRST, but it looks really bright compared to the one on the kick off video.
Ya our paint is a pretty bright green. It also isn’t a complete solid color but I believe that is because we did not use primer on that. It looks a lot different, but I think that is because of the lighting on the tetra and the image of the tetra through the camera (CMUCam2 and the video camera recording the kickoff).