In the above photo, my customer's lawn is on the right. You can see (I hope) the slight difference in hues.
Above, is a photo of the next door neighbor's lawn.
In the above photo, customer's lawn is on the left. The lawn on the right is the one photo'd above.
My customer's lawn is the thickest in the area. He mows fairly high and doesn't remove clippings (just what he does....not saying, at all, that this is incorrect). I will say that he waits until the lawn is high....and routinely has clippings lying on top (after he mows).