I would have converted the model output to [0, 255]  instead. However, you’ll have to make sure that your targets / labels are also in the same range. There is no advantage of using an input with [0, 255] over [0, 1], as the model weight parameters will adapt to whatever input range, it is a scaling factor as you can see. However, the common practice and the best performance can be obtained when the input is normalized to [0, 1] or [-1, 1].