Convert Kelvin to grayscale color

// kelvin values are around 270-290 normally for room temperature
// we have to scale up those, so we multiply by 10
public Color KelvinToGrayscaleColor(int kelvin)
{
    kelvin *= 10;
    var min = 2200;
        var max = 3800;
    var highestBit = 255;

    var result = 0.0;
    if (item <= max && item >= min)
    {
        result = ((double)(highestBit) / ((double)(max - min))) * ((double)(item - min));
    }

    return new Color(result, result, result)
}