Cant get my texture to show color changes

Am trying to show noise on a 2d texture the size of the window.
This is the code i am using:

        for(int xpos = 0;xpos < width;xpos ++)
        {
            for(int ypos = 0;ypos < height;ypos ++)
            {
                float value = (float)GetNoiseAt(xpos, ypos, 50) * 255;
                Debug.WriteLine(value);
                colourMap[colcounter] = new Color(value, value, value, 255);

                colcounter++;
            }
        }
        map.SetData(colourMap);
        return map;

I have logged the variable value in debug and i get values from 100 - 255 ish, however when i run it and display this to the window using spritebatch.draw i only see a very bright red presumably (255, 0, 0) with no variation in color despite by debug saying there are other colours. Im new to this and im sure ive made a basic mistake but i cant figure this out.Thanks in advance.

You are passing floats instead of ints, so it probably expects a 0…1 range.

Thanks, that seems to sort it