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Different cameras, screens, and screen settings have vastly different colour, hue, brightness, saturation, and contrast values. Those differences mean that virtual makeup appears different on each one. If you calibrate entirely on one device that is NOT the target users' device(s) it won't be consistent. Finalise on the actual devices make/model(s) you intend users to view the makeup on.
Lighting greatly affects virtual makeup as it can change the tone of people because of colour/temperature. Those differences mean that virtual makeup appears different in different environments. If you calibrate entirely in one environment that is NOT the target users' environment(s) it won't be consistent. Finalise in as close to the actual environment(s) you intend users to view the makeup in.