Sound to me like the light you use the unit in is what makes the difference as to what color it appears. 1. Using a digital camera with no filters in regular incadescent light(standard light bulbs) gives a GREEN LCD in the picture.
2. Using the 780 in the same normal light gives an AMBERISH YELLOW color display.
3. Using the unit under Flourescent lighting conditions, such as at work gives an orangish appearance.
4. Using it in daylight gives an orange appearance.
There is only one color of LCD it just looks different depending on what type of light you have the unit in when using it.
Take care.
Wayne.