OpenCV SURFDetector Range of minHessian

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I'm using the OpenCV SURFDetector to search for keypoints in an image. In my program I want to give the user the opportunity to set the value of the minHessian with a trackbar, but this would mean that I would have to know the range of the hessian-values.

I know that the higher I set this threshold the less keypoints I get and vice versa.

Is there a way to calculate a range of the hessian values so I can set 0 (which would be a very high minHessian threshold) on my trackbar to “no keypoints” and 100 (which is probably minHessian=1 or 0) for “all possible keypoints”?

I've already asked this question on stackoverflow if you prefer answering there (or on both sides): http://stackoverflow.com/questions/22009556/opencv-surfdetector-range-of-minhessian