matlab - Detected SURF Feature location -

i using surf on image size of 60*83 varying scale levels , metricthreshold generate more blobs. location of points2 vector showing coordinates beyond dimension of input image size. wonder why is. need obtain exact coordinate of detected key-points.

i2 = rgb2gray(temp);                          %i2= 60*83 uint8 points2 = detectsurffeatures(i2,'numscalelevels',6,'metricthreshold',600); 

i trying location of detected points in command window , showing following coordinates (see highlighted x-axis coordinate exceeding dimension). if use following code coordinates inside image dimension.

points2 = detectsurffeatures(i2); 

i need using varying scale levels , metricthreshold. in advance.

matlab stores matrix nofrows x nofcols

detectsurffeatures returns positions [x,y]

http://www.mathworks.com/help/vision/ref/surfpoints-class.html

so results in range.