LightingUniverse
In general, the length of the picture light shade should be about half of the width of the picture.
You’ll want to make this decision based on the power source you will be using.
This will vary depending on the particular light that you buy. It should be high enough above the picture that it does not obstruct the picture from the viewer and the bulb should be positioned so the viewer cannot see it directly.
Ultraviolet and infrared lights may damage art, so avoid those types of lights. For best results, use a true daylight bulb with a color temperature between 3,500K and 4,100K.
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