I have been asked to contour the peak PID readings for 32 sample locations. I have a point shape file with each locations peak PID value. The values range from 0.2 - 1305. I cannot get a logical solution when contouring. I've tried interpolating every way as well as creating a tin first, then to raster, then to contour. With the IDW method I get contour circles around many of the points. It makes sense but I have an inkling that the range of the values is just to broad. All but 3 of the 32 values are below 50 and the ones above are 103, 120, and 1305. Does anybody have an idea as to what the best method would be to contour these values?
do you have a labelled plot of the data and its distribution? I have a funny feeling that the data itself and any method to interpolate it prior to contouring is the real problem. It is neigh on impossible to get a 'reasonable' plot from 'unreasonable' data since there is no magic interpolator...which is the prior step to contouring.