It was also used for tinting and shading in early photography. This resulted in lash tinting, lash extensions, lash embroidery, and fake lashes. Staining differentiates tissues by tinting them in contrasting colours. Tinting and toning are important factors in film restoration today. The original prints featured color tinting. Rear taillights received subtle tinting, and the front fascia was redesigned. This has the effect of tinting the light the color of the dust particles. The Technicolor Corporation continued to experiment with both tinting, toning and colorizing. The principal use of ochre is for tinting with a permanent color. Eventually the rise of color film would make manual tinting obsolete. Hemocyanin contains two copper atoms, tinting the haemolymph with a faint blue color. Tinting and toning were sometimes applied together. Hand-colouring should be distinguished from "tinting", "toning", "retouching", and "crystoleum". Striking effects could be achieved by both tinting and toning sequences. Early techniques included hand tinting&colon; painting each frame by hand.