poisson random variable and adding noise to it,

Hi, I have a 2d poisson random variable to wchi i give a mean value and i am looking at the graph which looks fine. But as soon as i add "j = imnoise(r, 'poisson')" the second plot i get is not right coz the value of the noise is 1.00 max, it doesnt go beyond that irrespective of the value of the poisson variable.

Here is the code. What am i doing wrong ?The noise should be square root of the corresponding x value at a given point.

%generating random poisson variable by providing mean values r = poissrnd(4.7,10,2) plot (r) j = imnoise(r, 'poisson') figure(); plot(j)