Turn off the Independent toggle so that all three channels are applied equally. This will give a grayscale appearance to the noise, which is what we want. Note that too much noise and the texture looks like concrete. Too little and it won't have the rough texture we expect reptiles to have. Either one will work.
Larger blurs smooth out the texture in the long run.
In this case, a blur of 9 pixels in the X direction and 7 pixels in the Y directions was used, which will leave the lumps of the texture close together, but allow me to keep the surface between the lumps smooth when I bump map it. The blurred images and its historgram. The levels have been adjusted now. Adjust the Levels to closely match the histogram, but not exactly. This increases the contrast in the blurred image, bringing out some of the details.- snapshot of levels dialog with before and after shots of the canvas window.